bonjour
3x-4x²+7x= -4x²+3x+7x= -4x²+10x
9x²+8-6x²-10 = 9x²-6x²+8-10 = 3x²-2
13+8x-7-x=8x-x+13-7=7x+6
x²-3x+2x-5x²= x²-5x²-3x+2x= -4x²-x
A=6(x+3)+(2x-3)(3x-5) = 6x+18+6x²-10x-9x+15 = 6x²+6x-10x-9x+18+15=6x²-13x+33
B=(8-3x)(4x+1)-x(x+2)=32x+8-12x²-3x-x²-2x= -12x²-x²+32x-3x-2x+8 = -14x²+27x+8
C=(2x+1)-(6x-1)(-3x+8)=2x+1-(-18x²+48x+3x-8)=2x+1+18x²-51x+8=18x²+2x-51x+1+8=18x²-49x+9
D=2x(4-7x)+(7x+5)(2x-6)=8x-14x²+14x²-42x+10x-30=8x-42x+10x-30= -24x-30
E=(3x+2)(x-5)-(x-5)=3x²-15x+2x-10-x+5=3x²-15x+2x-x-10+5=3x²-14x-5
F=3(7x²+2x-8)-(4x+1)(5-9x)=21x²+6x-24-(20x-36x²+5-9x) = 21x²+6x-24-20x+36x²-5+9x = 21x²+36x²+6x-20x+9x-24-5=47x²-5x-29
