Question

When you multiply a difference of two squares (a+b)(a-b), why is your answer a binomial instead of a trinomial like when you multiply the sum of two squares (a+b)(a+b)?

Answer 1

Answer:

You get a binomial in both cases.

Multiplying a difference of squares:

a(x2 - y2) = ax2 - ay2

Multiplying a sum of squares:

a(x2 + y2) = ax2 + ay2

There is no trinomial here.