Réponse :
Bonjour :)
A = -2(x+5) = -2*x -2*5= -2x-10
B=3(5x-7)=3*5x3*(-7)=15x-21
C=4x(2x+1)=4x*2x+4x*1=8x²+4x
D=5(x+6)(4-3x)=5(x*4+x*(-3x)+6*4+6*(-3x))= 5(4x-3x²+24-18x) =5(-3x²-14x+24) =-15x²-70x+120
E=(x+1)(5-x)=x*5+x*(-x)+1*5+1*(-x)=5x-x²+5-x=-x²+4x+5
F = (5-2x) (3-x)=5*3+5*(-x)-2x*3-2x*(-x)=15-5x-6x+2x²=2x²-11x+15
