Réponse :
Explications étape
ex 1
A+B+C +36 CADEAUX
X+(X-4)+ 2(x-4) =36
x+x-4 +2x-8 = 36→→→→ 4x -12=36 →→→4x = 48 →→→x= 48/4 =12
boite A= 12
boite b = 12 -4 =8
boite c ) 2 *8 =16
a +b+c = 12 +8 + 16 =36
ex2
(2x+3)2 + 2( 3x+1) =28 →→→4x+6 + 6x+2 =28 →→→10x+8 = 28
10x = 28-8 →→→→10x = 20 →→→→ x =20/10 = 2
largeur = 2*2+3 = 7
longueur = 3*2+1 =7
Donc oui, c est un carré
ex3
farid = x
olivier = 2/3 x
Donc, 75 - (x+x*2/3 ) =11
75 - (3x/3 +2x/3 ) =11
75-5x/3 =11
-5x/3 = 11-75 →→→→→-5x/3 =-64 →→→→x= 64/ 5/3 =64/1 * 3/5 = 192/5
x= 38.4 euros donc farid = 38.4 euros
Olivier 2/3 de l argent de farid donc = 38.4* 2/3 =25.6 euros
résumons 75 - ( 38.4+ 25.6 ) = 11
Adam
