A= (2t-5)(t-8) + (2t-5)(4t-1)
A = (2t-5)(t-8) +(4t-1)
A = (2t -5)(t-8+4t-1)
A = (2t-5)(5t -9)
B= (5x-2)(3x+7) + (7x-3)(2-5x)
B =- (5x -2) (3x +7) + (7x -3)(2-5x)
B = (-5x +2) ( 3x+7) + (7x -3)(2-5x)
B = (-5x+2)(3x+7)+(7x-3)
B = (-5x+2)(3x+7+7x-3)
B = (-5x+2)(10x +4)
Resoudre les equations :
(7a-21)(2a+3) = 0
ou 7a-21 = 0 donc 7a = 21 et a = 3
ou 2a +3 = o donc 2a = -3 et a = -3/2
(5x-2)au carré = 49
5x -2 = 7
5x = 7 +2
5x = 9
x = 9/5
