Réponse :
Bonjour
Explications étape par étape
Question 1
A = 4x ( 8x -7) + (4 -3x) (5 +3x)
A = 32x² -28x + 20 +12x -15x -9x²
A = 23 x² -31x +20
Question 2
Factorisation
B = (5 +2x)(4 +3x) - (5 +2x) (7 +x)
B = (5 +2x) (4 +3x -7 -x)
B = (5 +2x) ( 2x -3)
Question 3
Equation
5 + 8 (3x -3) = 4x -9
5 +24x -24 = 4x -9
+24x -4x = -5 +24 -9
+20x = 10
x = 10/20
x = 1/2
