Bonsoir,
Développer les expressions:
2(5-2x)-2x(4+5x)= 10-4x-8x-10x²= -10x²-12x+10
7x(3x-2)-2x(-6+x)= 21x²-14x+12x-2x²= 19x²-2x
-4(x+3)+5(6+x)= -4x-12+30+5x= x+18
6x(3x+4)-4(5x+3)= 18x²+24x-20x-12= 18x²+4x-12
