Question

Simplify (a + b + c)(a + b - c) ​

Answer 1

Step-by-step explanation:

(a+b+c)(c+b−c)

Expand (a+b+c)(a+b−c) by multiplying 

each term in first expression by each term in second expression

a2+ab−ac+ba+b2−bc+ca+cb−c2

a2+ab+ba+b2−ac+ca+cb−bc−c2

a2+2ab+b2−0+0−c2

a2+2ab+b2−c2

(a+b)2−c2