Răspuns:
Explicație pas cu pas:
a) (x+2)(7x+x+2-3)=(x+2)(8x-1)
b) (y+3)(y+2+4y+12-4y)
=(y+3)(y+14)
c) (y+5)(3y-7-4y+2+3)=3x
=(y+5)(-y-2)
d)(3x-5)(3x-5-2x+1+6x)
=(3x-5)(7x-4)
e)(3x-2)^2(5x-4-1+2x+4)=
=(3x-2)^2(7x-1)
f)(5z-4y)(-2y-z-3y+z+5z-4y)
=(5z-4y)×0=0