Réponses

2014-02-21T00:04:19+01:00
A=3(-2x+5)+(-2x+5)(x-3=
A=-6x+15-2x²+6x+5x-15=-2x²+5x

B=(2a-5)(3-4a)-2(5-a)
B=6a-8a²-15+20a-10+2a=-8a²+28a-25

C=-(3-4z)(2-2)=-(3-4z)*0=0

D=-5r(2-3r)+(-r-2)(2r+r)
D=-10r+15r²-2r²-r²-4r-2r=12r²-16r