Pythagorean Theorem Practice

Skill: pythagorean-theorem

Pythagorean Theorem Practice

An endless supply of never-repeating right-triangle problems with instant feedback. Find hypotenuses and legs, simplify radicals, spot Pythagorean triples, and solve the word problems where a² + b² = c² earns its keep.

1 Practice

Type your answer and press Check answer (or Enter). A wrong answer earns a hint first; a second miss walks you through the full solution.

Score 0 · Streak 0 · Problem 0
Score counts first-try correct answers. Streak counts consecutive correct answers.
Right triangles

How to enter answers

  • Whole numbers and decimals: 10, 8.06 — decimals are accepted within ±0.01.
  • Radical answers: type sqrt53, √53, or 2sqrt10 for simplified form — or type a decimal. Both are accepted.
  • Yes / no questions: just type yes or no.

2 What you’ll practice

Every problem is generated fresh from 12 templates — a problem never repeats until its whole pool is used up.

Missing sides

Find the hypotenuse (add the squares, then root) or a leg (subtract, then root). c is always the hypotenuse — the longest side.

Legs 6 and 8 → c = 10

Exact radical form

When the answer is not a whole number, leave it exact: simplify the radical (type sqrt53 or 2sqrt10) or give a decimal.

Legs 2 and 7 → √53 ≈ 7.28

Triples & word problems

Spot Pythagorean triples, test whether a triangle is right, and solve ladder, diagonal, and screen-size problems.

9-ft ladder, 4 ft out → √65 ≈ 8.06 ft

3 Watch out for these

The three mistakes students make most often on Pythagoras problems.

1. Answering 100 instead of 10

Wrong: legs 6 and 8 → c² = 100, so “c = 100.”    Right: c = √100 = 10. The theorem gives you c² — the last step is always the square root.

2. Using a² + b² = c² on a non-right triangle

Wrong: applying it to any triangle with two known sides.    Right: right triangles only — look for the right-angle mark first.

3. Calling a leg “c”

Wrong: hypotenuse 13, leg 5 → 5² + 13² = b².    Right: 5² + b² = 13² → b = 12. c is always the hypotenuse.

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