Factoring differences of squares

The  exercise appears under the Algebra II Math Mission. This exercise practices factoring quadratic expressions of the general difference of squares form: $$(ax)^2-b^2$$. The factored expressions have the general form $$(ax+b)(ax-b)$$.

Types of problems
There are two types of problem in this exercise:
 * 1) Which student wrote an expression that is equivalent to ___ ?: This problem has two students that were each asked to factor a quadratic expression and the user is asked to find which student(s) had an expression equivalent to it.
 * 2) What binomial factor do they share?: This problem has two polynomial expressions that share a common factor. User is asked to find which binomial factor they share.

Strategies
Basic knowledge of addition is required for this exercise.
 * 1) User can factor expressions by using the difference of two squares pattern, for __ = __ and __ = __.

Real-life Applications

 * 1) Square roots are used in Pythagorean's Theorem, which states that $$a^2+b^2=c^2$$.