Question

Simplify (a + b + c)(a + b - c).

Answer 1

ANSWER:

(a+b)² - c²

Step-by-step explanation:

by using x²-y² = ( x + y) ( x - y) identity

take x = (a+b)

and y = c

Answer 2

Answer:

a(a+b-c) + b(a+b-c) +c(a+b-c)

=a^2 + ab - ac + ab + b^2 - bc + ac + bc - c^2

=a^2 + b^2 - c^2 + 2ab