Practice Factoring Difference of Squares in Math

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

Recognizing and factoring expressions of the form a^2 - b^2 into the product (a + b)(a - b).

When you multiply (a + b)(a - b), the middle terms cancel: a^2 - ab + ab - b^2 = a^2 - b^2. So any time you see a perfect square minus a perfect square, you can instantly factor it. Think of it as a rectangle whose area is the difference of two square areas.

Example 1

easy
Factor x^2 - 49.

Example 2

medium
Factor 16x^2 - 25y^2.

Example 3

easy
Factor x^2 - 1.

Example 4

hard
Factor x^4 - 81 completely.