Question

Simplify (x + y + z) (x + y – z)​

Answer 1

Answer:

(x+y+z)(x+y-z)

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

= x²+xy-xz+xy+y²-yz+xz+yz-z²

= x²+xy+xy+y²-z²

= x²+2xy+y²-z²