Solving quadratics by square roots worksheets

Some quadratics do not need factoring: when the equation is already a square, you isolate it and take the square root of both sides. These free printable worksheets solve x² = p, ax² = c and (x − h)² = k that way — and every one has two answers.

Solving quadratics by square roots
Solving quadratics by square roots worksheet — x² = p, ax² = c, (x − h)² = k, free printable with answer key

The answer key prints on a separate page.

What's on this sheet

This is the square-root method, the companion to the factoring sheets. The equation arrives as a square, so there is nothing to factor: for x² = 49 you take the root of both sides and get x = ±7; for 3x² = 48 you divide by 3 first, then root; for (x − 2)² = 9 you root both sides to x − 2 = ±3, then add 2. The one thing to keep is the ±, because a positive number has two square roots and the answer is both.

Why this sheet works

It comes a step before factoring and stays beside it: the factoring sheets take x² + bx + c = 0, which these never print, and these take the square forms, which those never print. A child who has met both knows which method a question is asking for by its shape.