Factor a difference of squares worksheets

x² − 64 is one square minus another, and it factors on sight into (x + 8)(x − 8). These free printable worksheets drill the plain difference of squares, no coefficient in front.

Factor a difference of squares
Factor a difference of squares worksheet — x² − k², whole k, free printable with answer key

The answer key prints on a separate page.

What's on this sheet

This is the one factorization with no search in it. There is no pair of numbers to hunt for and no middle term to match — the expression is one perfect square take away another, and it splits into the sum times the difference. What a child has to see is the shape: is each part a perfect square, and is the sign a minus.

Why this sheet works

The shape is exactly where the mistakes live. x² + 64 is a sum and does not factor at all, and x² − 20 is not a difference of squares because 20 is not a perfect square. A child who has learned the shortcut reaches for it on both; every walk here checks the two conditions before it factors anything.