Sagot :
1) 4(5x - 3) + (2x - 1)(x + 4)=20x-12+2x^2+8x-x-4=2x^2+27x-16
2) 3x - x(4x + 1) + (-x + 2)(5 - 4x)=3x-4x^2-x-5x+4x^2+10-8x=-11x+10
3) (2x + 3)(-2x + 7) - (3x - 4)(2 + 5x)=-4x^2+14x-6x+21-6x-15x^2+8+20x=-19x^2+22x+29
bonne chance
1) 20x-12+2x²+8x-x-4=2x²+27x-16
2) 3x-4x²+x-5x+4x²+10-8x=-9x+10
3)-4x²+14x-6x+21-(6x+15x²-8-20x)= -4x²+8x+21-6x-15x²+8+20x=-19x²+22x+29