Question

rezolvati:)) nu imi dau seama la prima paranteza ce trebuie sa fac

Answer 1

2x+2y-2z (x+y-z) =>(x+y-z)

Answer 2

$=(x+y-z)(x+y-z)-( x^{2} +2xy+ y^{2})-( y^{2} +2zy+ z^{2})=$

$x^{2} +xy-xz+xy+y ^{2}-yz-xz-yz+ z^{2} - x^{2} -2xy- y^{2}- y^{2}-2yz- z^{2}$

=-2xz-y²-4yz