Réponse :
A = 5x-3(x+12)
= 5x - 3x - 36
= 2x - 36
B = 3x-6+7(2x+4)
= 3x−6+14x+28
= (3x+14x)+(−6+28)
= 17x+22
C = [tex]2x^{2}[/tex]+x(4x-5)
= [tex]2x^{2}[/tex]+[tex]4x^{2}[/tex]−5x
=( [tex]2x^{2} + 4x^{2}[/tex])−5x
= [tex]6x^{2}[/tex] -5x
D= [tex]4x^{2}[/tex]-x+x(5x-9)
= [tex]4x^{2} - x + 5x^{2} - 9x[/tex]
= [tex]9x^{2} -10x[/tex]
