bonjour pouvez vous m'aider svp

A=3(2x-6)-(3-5x)
A=6x-18-3+5x
A=11x-21
B=(5-2y)-(-3y+7)
B=5-2y+3y-7
B=y-2
C=4(6+z)+(z-3)(2-z)
C=24+4z+2z-z²-6+3z
C=-z²+9z+18
D=(2t-5)(3t+2)-(t²+6)
D=6t²+4t-15t-10-t²-6
D=5t²-11t-16

A=3(-2x+5)+(-2x+5)(x-3)
A=-6x+15-2x²+6x+5x-15
A=-2x²+5x
B=(2a-5)(3-4a)-2(5-a)
B=6a-8a²-15+20a-10+2a
B=-8a²+28a-25
C=-(3-4z)(z-2)
C=-(3z-6-4z²+8z)
C=-3z+6+4z²-8z
C=4z²-11z+6
D=-5r(2-3r)+(-r-2)(2r+5)
D=-10r+15r²-2r²-5r-4r-10
D=13r²-19r-10