Grade 8 / Literal expressions: equalities, distributivity 79 exercises (100% corrected)

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ABCD32x Programme AChoisir un nombreSoustraire 2Multiplier par4Elever au carréAjouter les deux nombresProgramme BChoisir un nombreCalculer son carréAjouter6au résultat ChingQuizz : 8 exercises available for Quizz assessment : 1. Calculation Using an Expression E.5655 Evaluate the following literal ex-pressions for x =2 : a 3 x + 2 b 2 × (3 x 1) c 2 x + 8 x + 1 E.5656 Evaluate the following literal expres-sions for x = 1 : a 4 x + 1 b 3 × (3 x + 1) c 9 3 x 9 + x E.8792 Evaluate the following literal expres-sions for x =2 : a x 2 + 1 b x x 2 c ( x + 2) 2 E.8793 Evaluate the following literal expres-sions for x = 1 : a x 2 + 1 b 2 x 2 + 2 x c ( x + 2) 2 E.4491 Using mental math, complete the table below, for each row an expression is evaluated for different values of x : x 0 1 3 2 2 x 3 x 2 2 x +3 2 x 2 4 2( x +4) 3 E.4520 Consider the expression : A = 2 x 2 +4 x +6 1 Evaluate the expression A for the values : x = 1 ; x =3 2 Tell whether the statement below is true or false. Justify your answer: ˇThe expression A is zero for any value of x 2. Modeling by an expression E.8795 Consider the rectangle ABCD shown below having length and width ( x +2) and 3 respec-tively: 1 Determine the perimeter and area of the rectangle ABCD when x =1 ? x =4 ? 2 a Give an expression, in terms of x , for the perimeter of the rectangle ABCD . b Give an expression, as a function of x , for the area of the rectangle ABCD . E.8794 Here are two calculation programs : 1 For program A : a Give the output value of program A when the input value is 3 ? is 1 ? b If the input number is denoted x , give an expression for the output value of program A. 2 For program B: a Give the output value of program B when the input value is 3 ? is 1 ? b If the input number is denoted x , give an expression for the output value of program B. https://chingmath.fr chapExoCorrec/5655 sacados/5655 chapExoCorrec/5656 sacados/5656 chapExoCorrec/8792 sacados/8792 chapExoCorrec/8793 sacados/8793 chapExoCorrec/4491 sacados/4491 chapExoCorrec/4520 sacados/4520 chapExoCorrec/8795 sacados/8795 ABCD32x chapExoCorrec/8794 sacados/8794 Programme AChoisir un nombreSoustraire 2Multiplier par4Elever au carréAjouter les deux nombresProgramme BChoisir un nombreCalculer son carréAjouter6au résultat
HABCDEFIG7cm xxx122x4x2x11 xxx335x22xx13 3. Simple discounts E.1908 Reduce, if possible, the writing of the following expressions : a 3 × x × 2 b 5 + x c 4 x + x + x d 3 x + 2 + x e 5 × x + x f 4 x +6+2+ x 3 x E.8791 Consider the polygon ABCDEF shown shaded below ABGF is a rectangle and CDEG is a square : 1 Give, without justification, the perimeter of polygon ABCDEF in the following cases : a DC =1 b DC =4 2 Consider the expression E defined by: E =14+4 x a Evaluate the expression E for each of the values of x below : x =1 ; x =4 b Noting x the length of segment [ DC ] , justify that the expression E still yields the value of the perimeter of the polygon ABCEF . 4. Discounts E.6305 Below are shown 6 rectangles and squares o where the letter x designates the same, undeter-mined measurement of some of the sides of these rectangles. Justify that the total area of these rectangles can be expressed using the following literal expression : 3 x 2 +5 x +5 E.6322 Below are shown 6 rectangles and squares x is an undetermined length but expressing the side length of some of these triangles. Give a simplified expression representing the total area of these six rectangles. E.8797 Definition: The action of reducing a literal expression is to ˇ count together ı similar terms in order to avoid repetition. (S. Baruk) Example: To reduce an expression, we group together terms of the same type : 5 + 2 a + 3 b + 4 b + 3 + 2 a = 2 a + 2 a + 3 b + 4 b + 5 + 3 = 4 a + 7 b + 8 Often, we use ˇ simplify ı instead of reduce. Reduce the following expressions : a 2 x + 5 4 x + 3 b 5 x + 4 x + 3 E.1922 Consider the two literal expressions below : a 5 4 x + 6 x 3 b x 2 + 5 x 4 + 3 x 5 x 2 + 7 4 x 8 1 Copy each of these expressions and then : underline in black the terms in x 2 ; underline in red the terms in x ; underline in blue the numeric terms. 2 Reduce these two expressions. E.8799 Reduce the following expressions : q x 2 + x + 3 x + 5 x 2 + 1 b 6 x 2 3+5 x 7 x 2 +4 2 x https://chingmath.fr chapExoCorrec/1908 sacados/1908 chapExoCorrec/8791 sacados/8791 HABCDEFIG7cm chapExoCorrec/6305 sacados/6305 xxx122x4x2x11 chapExoCorrec/6322 sacados/6322 xxx335x22xx13 chapExoCorrec/8797 sacados/8797 chapExoCorrec/1922 sacados/1922 chapExoCorrec/8799 sacados/8799
ABCD32x E.6321 Reduce the following expressions : a 3 x +2 2 x 2 +5 x +4 x 2 5 b 2 x + x 2 5 x 2 +3 x 2 E.8923 Simplify the following expressions : a 5 x × 2 x 3 x × 2 x × 2 x + 5 × 2 x b 3 × 2 x × 3 + 2 x × x 5 x 2 E.8798 Reduce the following expressions : a 2 x × 3 x 2 × 4 x + 5 × 2 3 × 3 x 2 3 2 b 5 × 2 x 3 × 4 + 3 x × 2 2 x × 3 x E.1080 Reduce the following expressions : a 2 x × 3 x +2 x +3 x 2 4 x b 2 × (3 x 2 ) (4 x ) × x + x 2 E.1928 Reduce the following expressions : a 3 x + 5 x × ( 2 x ) + x × 2 b 2 + 3 × 4 x x c 3 × 2 + ( x × 5) × 3 + x × 2 x d ( x ) × ( x ) + ( x ) × x E.4519 Reduce the following expressions : a 2 × 5 x × x + 4 × ( 3) + 3 × ( 2 x ) b x × ( 3 x ) + 7 × 3 2 x × ( 2) 3 × ( 2 x 2 ) E.62 Expand and simplify the following ex-pressions : a 5 × x + ( 3) × 2 x + x × 2 x b 2 x × ( 2 x ) + ( x 2 ) × ( 2) c ( 3) × x + ( 2 x ) × (+2 x ) + x 2 × 3 5. Factoring and calculation E.8954 Use distributivity to calculate the following expressions : a 13 × 7 + 13 × 3 b 12 × 5 + 8 × 5 a 3 × 7 + 3 × 3 E.5657 Using a mental calculation, give the value of the following calculations : a 12 × 17 + 12 × 3 b 15 × 19 5 × 19 c 23 × 81 3 × 81 E.8813 Use distributivity to calculate the following expressions : A 18.87 × 32.7 + 18.87 × 56.5 + 18.87 × 10.8 b 19.67 × 19.67 19.67 × 9.67 6. Development and calculation E.4492 Using a mental calculation, give the value of the following calculations : a 11 × 15 b 21 × 33 c 31 × 16 E.1253 Perform the following calculations, leaving the steps of your calculations : A 101 × 347 b 98 × 240 E.8955 Using a mental calculation, give the value of the following calculations : a 9 × 37 b 9 × 32 c 19 × 64 E.1226 Clever calculation: A 101 × 347 b 98 × 240 7. Distributivity: development E.4512 Consider the rectangle ABCD shown below having length and width ( x +2) and 3 respec-tively: 1 Determine the area of the rectangle ABCD . 2 By hatching the representation of ABCD , highlight the following equality: A = 3 x + 6 E.1910 Expand and reduce the following expressions : a 3 × (2 x + 4) b x × (2 x 1) c (3 2 x ) x d x × (3 + x ) https://chingmath.fr chapExoCorrec/6321 sacados/6321 chapExoCorrec/8923 sacados/8923 chapExoCorrec/8798 sacados/8798 chapExoCorrec/1080 sacados/1080 chapExoCorrec/1928 sacados/1928 chapExoCorrec/4519 sacados/4519 chapExoCorrec/62 sacados/62 chapExoCorrec/8954 sacados/8954 chapExoCorrec/5657 sacados/5657 chapExoCorrec/8813 sacados/8813 chapExoCorrec/4492 sacados/4492 chapExoCorrec/1253 sacados/1253 chapExoCorrec/8955 sacados/8955 chapExoCorrec/1226 sacados/1226 chapExoCorrec/4512 sacados/4512 ABCD32x chapExoCorrec/1910 sacados/1910
E.8810 Expand and reduce the following expressions : a 3 × (2 x + 1) b x + (2 x 1) × 2 E.1251 Consider the following two expres-sions : The product of 3 by the sum of x and 2 . The sum of the product of 3 by x and 6 . Justify that these two expressions are equal. E.1249 In the following two calculations, use distributivity to give the following expressions in their developed and reduced forms : a 7 × (2 x + 5) + 4 b 3 × (3 + x + 2 x + 12 E.8925 Expand and reduce the following expressions : a x + 2(2 x 1) b 3 3 x + x × (3 x + 1) E.8812 Reduce the following expressions : a 2(3 + x ) + (2 + x ) × 4 b 2(3 + x ) + 5 + 2( x 1) E.8814 Write the literal expressions below in their expanded and reduced forms : a 2 1 + x x 2 b x 1 + 2 x + 1 8. Distributivity: factoring E.8816 Using distributivity, transform the writing of the following expressions to show their factorized forms : a 5 x 5 × 3 b 3 x + 12 E.4548 Factor the following expressions : a 4 x + 2 b 5 15 x c 4 x 6 E.6344 Factor the following expressions : a 12 x + 15 b 12 x + 20 c 3 x + 6 E.8815 Give the factorized form of the fol-lowing expressions : a 2 × x + 2 × 4 b 25 x + 15 E.1909 If possible, factor the following ex-pressions : a 3 × x + 9 b 5 x + 5 c 5 x + 25 E.8811 Factor the following expressions : a x 2 + 2 x b 3 x 2 2 x c 4 x 2 + x E.8821 Factor the following expressions : a 5 x 2 x b 6 x 2 + 3 x c 8 x + 16 x 2 E.8927 Factor each of the following expres-sions : a 5 x + 15 b 7 x + 2 x 2 E.8822 Factor, if possible, the following ex-pressions : a 3 × x + 9 b x × x + 3 x c 5 x + x d 5 x + 25 e 3 x 2 + 9 x f 6 xy + 12 x E.4522 Factor the following expressions : a 3 × x + 6 b 4 x 2 3 x c 15 x 2 + 5 d 5 x 2 + 4 x e 6 x 2 + 9 x f 12 x 2 4 x 9. Modeling, development, reduction E.5659 The following calculation program is considered : Choose a number; Multiply it by 2; Add 3 ; Multiply by 2 ; Subtract 6 1 Noting x as the starting number, give the expression con-structed by this calculation program. 2 a Without justification, complete the table below : Nombre d’entrée 1 0 4 2 Number returned b Can we conjecture a new expression that would repre-sent this calculation program? c Justify your previous remark. For this last question, any trace of research will be considered. https://chingmath.fr chapExoCorrec/8810 sacados/8810 chapExoCorrec/1251 sacados/1251 chapExoCorrec/1249 sacados/1249 chapExoCorrec/8925 sacados/8925 chapExoCorrec/8812 sacados/8812 chapExoCorrec/8814 sacados/8814 chapExoCorrec/8816 sacados/8816 chapExoCorrec/4548 sacados/4548 chapExoCorrec/6344 sacados/6344 chapExoCorrec/8815 sacados/8815 chapExoCorrec/1909 sacados/1909 chapExoCorrec/8811 sacados/8811 chapExoCorrec/8821 sacados/8821 chapExoCorrec/8927 sacados/8927 chapExoCorrec/8822 sacados/8822 chapExoCorrec/4522 sacados/4522 chapExoCorrec/5659 sacados/5659
ABCDEFGHMNxcm7cm x22x3xABCDNMP E.1241 A notebook costs x pesos and a binder costs 5 pesos more than a notebook. 1 Given x the price of a notebook, establish a literal ex-pression as a function of x representing the following pur-chase : 5 binders and 4 notebooks 2 Reduce the expression obtained in question 1 . E.5700 All calculations and any record of research, no matter how incomplete, will be con-sidered in the evaluation. Marc and Sophie are challenging each other with math. It’s Marc’s turn ; he proposes a calculation program to his class-mate : Choose a positive integer Square this number Add 3 to the result Then multiply by 2 the result obtained Subtract 6 from the previous result Finally, take half of the last result Write the final result Sophie announces that we can go from the originally chosen number to the final number in one step. Is she right? E.6315 ˇ I take a whole number, add 3 to it, and multiply the result by 7 . I add three times the starting number to the result and remove 21 . I still get a multiple of 10 . ı Is this true? Justify. Any trace of research, even if incomplete, will be con-sidered in the assessment. 10. Areas, development, reduction E.1863 We want to study the area of the polygon ABCDEFGH shown below, where ABMN is a rect-angle and FGHN and CDEM are squares : The measurement FE =7 cm is given, and we denote the mea-surement of segment [ CD ] by x . 1 Complete the table below without justification : Value of x 2 4 Area A of polygon ABCDEFGH 2 a Using the polygon division proposed in the state-ment, show that the area A can be expressed as : A = 7 + 2 x × x + 2 x 2 b Propose another division that allows you to justify that the area A can also be expressed by the expression : A = 4 x 2 + 7 x Hint: you can justify this last question either by reduction or by a different area calculation E.1252 Consider the shaded ABCMNP polygon below : the quadrilaterals ABCD and MNPD are rectangles and x is the length of the segment [ AP ] : 1 Give the expression for the perimeter of the polygon ABCMNP in terms of x . Give this literal expression in its expanded and reduced form. 2 Calculate the perimeter of the figure in the cases x =5 https://chingmath.fr chapExoCorrec/1241 sacados/1241 chapExoCorrec/5700 sacados/5700 chapExoCorrec/6315 sacados/6315 chapExoCorrec/1863 sacados/1863 ABCDEFGHMNxcm7cm chapExoCorrec/1252 sacados/1252 x22x3xABCDNMP
3cm3cm5cm3cm3cm5cmxcmABCDEFGHIJ HABCDEFIGxcm7cm E.1880 Consider the polygon ABEFGHIJ formed from the rectangle ABCD from which the two squares DHIJ and CEFG of side x cm have been removed. 1 Reproduce this figure for x =1.5 cm . 2 a Determine as a function of x the perimeter measure of this polygon. Give the reduced form of this expres-sion. b Deduce the measure of this perimeter for x =1.5 cm . 3 a Give the measure of the area of the polygon ABEFGHIJ for x =1.5 cm . b Write a literal expression representing the area of this polygon. 11. Equality of expression E.1887 Consider the polygon ABCDEF shown shaded below where ABGF is a rectangle and CDEG is a square : 1 Using two distinct geometric reasonings, show that the area A admits the following two expressions : A =7 x + x 2 ; A = x 2 + x 2 + 7 x × x 2 a Complete the table of values below : Value of x 1 3 Polygon area ABCDEF b Check that the values obtained are valid whatever the expression used. E.1240 1 Consider the following two expressions : A =5 x +3 ; B =8 x a Complete the table of values below : Value of x 1 2 Value of A Value of B b Can we say that the expressions A and B are equal? 2 Consider the following two expressions : C =8 x +4 ; D =4 × 2 x +1 a Complete the table of values below : Value of x 2 3 Value of C Value of D b Can we say that the expressions C and D are equal? What can we do to be sure? Note: To show that two expressions are different , we look for a value of x for which these two expressions have different results. To show that two expressions are equal , we must show that they have the same expanded and simplified forms. E.1324 Indicate whether the following equa-tions are true or false. Explain your answer! a 3 x + 9 = 3 × ( x + 3) b 3 × (2 x + 3) = 6 x + 5 E.8820 Say whether the following equalities are true or false. Justify! a 5 x + 3 = 8 x c 8 x + 4 = 4 × (2 x + 1) E.1225 Explain why these equalities involv-ing literal expressions are false : a 3 × (2 x + 1) + 3 = 5 x + 6 b 2 x + 2 × ( x + 2) = 6 x + 2 https://chingmath.fr chapExoCorrec/1880 sacados/1880 3cm3cm5cm3cm3cm5cmxcmABCDEFGHIJ chapExoCorrec/1887 sacados/1887 HABCDEFIGxcm7cm chapExoCorrec/1240 sacados/1240 chapExoCorrec/1324 sacados/1324 chapExoCorrec/8820 sacados/8820 chapExoCorrec/1225 sacados/1225
2x63xx2362 Choisir un nombreCalculer son carréAjouter6au résultat Choisir un nombreSoustraire 2Multiplier par4Elever au carréAjouter les deux nombres E.1239 Which of the following equalities are true or false? Justify : a false equality by a counterexample; a true equality by development and reduction of literal expressions. a 2 + 2 x = 4 x b 3 × ( x + 5) = 3 × x + 15 c 2 × (2 + 3) = 2 x + 6 d 5 a + 35 = 5 × (5 a + 7) e 3 × ( x + 2) + 2 × (5 x 1) = 13 x + 4 E.8817 Study the literal expressions below. Justify : a 3 × (2 x + 4) = 6 x + 12 b 5 x + 13 = 5 × ( x + 2) + 3 E.8818 Tell us if the following equations are true. Justify your answer. a (2 x + 1) × 3 + 2 × (3 x + 2) = 12 x + 7 b x + 15 + 3 x + 7 x + x + 23 1 x 8 = 11 x + 30 E.8819 Tell if the following equalities are true or false. Justify! a (2 x + 1) × 3 + 2 × (3 x + 2) = 12 x + 7 b x + 15 + 3 x + 7 x + x + 23 1 x 8 = 11 x + 30 12. Modeling: equality of expressions E.6323 We note x a length that is not yet determined. From this length, we construct the two figures below : Justify that these two figures have the same area regardless of the value of x . 13. To the equations E.8695 We consider the calculation program : 1 What is the result of the program B if we choose the number 5 ? 2 If we note x the number chosen as the input to the algo-rithm, justify that the number returned by is expressed as x 2 +6 . 3 Determine the input value so that this calculation pro-gram returns as an output value 31 . E.8796 Consider the calculation program shown in the diagram below : 1 a Noting x as the number provided as input to this cal-culation program, give an expression giving the num-ber returned by this calculation program. b We wish to evaluate the two expressions ˇ x 2 +4 ı and ˇ 4 x + x 2 2 ı for certain values of x : x 2 0 3 4 x + x 2 2 x 2 0 3 x 2 +4 2 a We look for the value of x such that the expression has the value 29 b Check the answers to question a . https://chingmath.fr chapExoCorrec/1239 sacados/1239 chapExoCorrec/8817 sacados/8817 chapExoCorrec/8818 sacados/8818 chapExoCorrec/8819 sacados/8819 chapExoCorrec/6323 sacados/6323 2x63xx2362 chapExoCorrec/8695 sacados/8695 Extrait Antilles-Guyanne Juin 2019 Choisir un nombreCalculer son carréAjouter6au résultat chapExoCorrec/8796 sacados/8796 Choisir un nombreSoustraire 2Multiplier par4Elever au carréAjouter les deux nombres
3xx2362 100150200250300350167250333417500583831251672082502925683111139167194426383104125146335067831001172842566983972436486071832131425263731928374656651725334250580,10,20,30,40,50,60,70,80,91vn E.1881 Jacques has two children, Paul and Marie. Paul is two years older than Marie. James is four times Mary’s age. 1 If Paul is 12 years old, give the ages of Mary and James. 2 We’ll note x Paul’s age. Give the expression for James’ age as a function of x . 3 What is Paul’s age, if James is 48? E.8836 We consider the figure below com- posed of three rectangles : Determine the value of x so that the area of this figure is 21 . 14. Share E.4534 1 Reduce the following expressions : a 3 x 2 5 + 6 x 8 x 2 + 4 x + 4 b 3 × 2 x 5 × 2 + x × ( 3 x ) ( 5 x ) × ( 2) 2 Expand and reduce the following expressions : a 3( x + 4) b 4(3 2 x ) + 2(5 x 4) 3 Factor the following expressions : a 6 x + 15 b 4 x 2 + 6 x E.1925 1 Expand and reduce the following expressions : a 3( x 2) b 2(6 x + 3) + x 2 Factor the following expressions : a 3 x + 9 b x 2 + 2 x E.1248 Using distributivity: 1 Give the developed and reduced form of the following literal expressions : a (3 x + 2) × 4 b 2.2 × (3 5 x ) 2 Give the factorized form of the following literal expres-sions : a 3.1 × 5 x 2 × 3.1 b 3 × x + 12 15. Unclassified exercises E.6359 Intravenous infusions are used to administer flu-ids and medications to patients. Nurses need to calculate the flow rate D of an infusion in drops per minute. They use the formula D = d × v 60 × n : d : is the flow factor in drops per milliliter ( m‘ ) ; v : is the volume (in m‘ ) of the infusion ; n : is the number of hours the infusion should last. 1 A nurse wants to double the duration of an infusion. Describe precisely how D changes if n is doubled and d and v do not change 2 Nurses must also calculate the volume v of the infusion based on the infusion rate D . An infusion with a flow rate of 50 drops per minute should be administered to a patient for 3 hours. For this infusion, the flow factor is 25 drops per milliliter. What is the volume in m‘ of this infusion? 3 A nurse sets the flow factor to 10 drops per milliliter. She then uses the table adapted to this setting and giv- ing the value of the parameter D of the number of drops per minuutes. Here’s the table : Knowing that she has to infuse a patient for a maximum of 1 = 2 h and that the rate D of drops per minute must not exceed 60 and given the values given in the table, what choice can she make for the volume ( v ) of the infusion and the number of hours ( n ) that the infusion will last? Justify your approach. https://chingmath.fr chapExoCorrec/1881 sacados/1881 chapExoCorrec/8836 sacados/8836 3xx2362 chapExoCorrec/4534 sacados/4534 chapExoCorrec/1925 sacados/1925 chapExoCorrec/1248 sacados/1248 chapExoCorrec/6359 sacados/6359 extrait de Pisa 100150200250300350167250333417500583831251672082502925683111139167194426383104125146335067831001172842566983972436486071832131425263731928374656651725334250580,10,20,30,40,50,60,70,80,91vn
4x14x1;52x de∏nirscript1demanderdonnerunevaleuretatteindrestyloenpositiond’écritureavancerde4*réponse+1,5tournerdeBdegrésavancerde2*réponsetournerde90degrésrépéterAfoisreleverlestylode∏nirscript2demanderdonnerunevaleuretatteindrestyloenpositiond’écritureavancerde4*réponse+1tournerdeDdegrésrépéterCfoisreleverlestylo quandestcliquédemanderàChoisissezunnombre?etattendreenvoyeràtouslenombreaétésaisimettreNombreàréponsemettreRésultat1à2*nombre+3mettreRésultat1àRésultat1*Résultat1direregroupelerésultatestRésultat1pendant2secondes QuandjereçoislenombreaétésaisimettreàRésultat2àNombre*NombremettreàRésultat2àRésultat2*4mettreàRésultat2àRésultat2+12*NombremettreàRésultat2àRésultat2+9attendre3secondesdireregroupelerésultat2estRésultat2 E.1362 Let A = 3 2 × 1 4 + 1 4 : 1 Calculate A by first calculating the parentheses. 2 Calculate A by first using distributivity. Give the results in simplified form. E.8899 Part 1 In this part, all lengths are expressed in centimeters. Consider the two figures below, an equilateral triangle and a rectangle, where x represents any positive number. 1 Construct the equilateral triangle for x =2 2 a Show that the perimeter of the rectangle as a func-tion of x can be written 12 x +3 . b For what value of x is the perimeter of the rectangle equal to 18 cm ? 3 Is it true that the two figures have the same perimeter for all values of x ? Justify. Part II We created the scripts (opposite) on Scratch that, after asking the user for the value of x , construct the two figures in Part I . In these two scripts, the letters A , B , C , and D replace num-bers. Give values to A , B , C , and D so that these two scripts construct the figures in part I and then specify the figure associated with each of the scripts. E.8942 Here is a script entered by Alice in an algorithmic software. 1 Alice chose 3 as her number, calculate the values of Result 1 and Result 2 ? Justify by showing the calculations performed. 2 Generalization. a Calling x the number chosen in the algorithm, give a literal expression translating the first part of the algo-rithm corresponding to Result 1 . b Calling x the number chosen in the algorithm, give a literal expression translating the second part of the algorithm corresponds to Result 2 . https://chingmath.fr chapExoCorrec/1362 sacados/1362 chapExoCorrec/8899 sacados/8899 4x14x1;52x de∏nirscript1demanderdonnerunevaleuretatteindrestyloenpositiond’écritureavancerde4*réponse+1,5tournerdeBdegrésavancerde2*réponsetournerde90degrésrépéterAfoisreleverlestylode∏nirscript2demanderdonnerunevaleuretatteindrestyloenpositiond’écritureavancerde4*réponse+1tournerdeDdegrésrépéterCfoisreleverlestylo chapExoCorrec/8942 sacados/8942 quandestcliquédemanderàChoisissezunnombre?etattendreenvoyeràtouslenombreaétésaisimettreNombreàréponsemettreRésultat1à2*nombre+3mettreRésultat1àRésultat1*Résultat1direregroupelerésultatestRésultat1pendant2secondes QuandjereçoislenombreaétésaisimettreàRésultat2àNombre*NombremettreàRésultat2àRésultat2*4mettreàRésultat2àRésultat2+12*NombremettreàRésultat2àRésultat2+9attendre3secondesdireregroupelerésultat2estRésultat2
12345678ABCDNombrechoisiRésultatavecleprogramme1Résultatavecleprogramme20-20-201-16-162-12-123-8-8456 E.8944 Here are two calculation pro-grams : Calculation program 1: Subtract 5 Multiply by 4 Calculation program 2: Multiply by 6 Subtract 20 Subtract double the start-ing number 1 a What result do we get when we apply the calculation program 1 to the number 3 ? b What result do we get when we apply the computation program 2 to the number 3 ? 2 Demonstrate that by choosing the number 2 , both pro-grams give the same result. 3 We decide to run more trials. To do this, a spreadsheet is used and the following screenshot is obtained : What formula could have been entered in cell B2 before copying it down to cell B5 ? 4 The results shown in the columns B and C are equal. Lucy then thinks that, for any number chosen at the beginning, both programs always give the same result. Show that Lucie is correct. E.5084 The following calculation program is proposed : Choisir a number. Subtract 6 . Calculate the square of the result. 1 a We choose the number 4 at the start, show that the result obtained is 100 . b We choose 15 as the starting number, what is the result obtained? 2 Noting x as a number, what expression gives the result obtained? E.5085 We consider the following two calcula-tion programs : Choose a number. Add 3 to that number. Multiply the result by 2 . View product. Choose a number. Multiply by 3 this number. Add 2 to the result. Display the sum. 1 a Quel (s) résultat (s) do you get with these two calcu-lation programs when the chosen number is 4 ? b Can we say that these two calculation programs are equivalent? 2 a What number must be chosen to obtain the number 18 by the first calculation program? b What number should be chosen to get the number 8 by the second calculation program? E.4612 Factor the following expressions : a 3 x + 6 b 2 x 8 c 27 x + 18 https://chingmath.fr chapExoCorrec/8944 sacados/8944 12345678ABCDNombrechoisiRésultatavecleprogramme1Résultatavecleprogramme20-20-201-16-162-12-123-8-8456 chapExoCorrec/5084 sacados/5084 chapExoCorrec/5085 sacados/5085 chapExoCorrec/4612 sacados/4612