How it works
Why the Pythagoras calculadora exists
A pythagoras calculadora saves you from squaring, adding and rooting by hand when you already know two sides of a right triangle. GCSE and A-level papers love ladder-against-a-wall, coordinate-distance and “is this triangle right-angled?” questions — all are Pythagoras in disguise.
Three worked examples
Find the hypotenuse — legs 6 cm and 8 cm
c = √(6² + 8²) = √(36 + 64) = √100 = 10 cm — the classic 6-8-10 triple.
Find a shorter side — hypotenuse 13 m, one leg 5 m
a = √(13² − 5²) = √(169 − 25) = √144 = 12 m.
Check if a triangle is right — sides 9, 12, 15
Test 9² + 12² = 81 + 144 = 225 = 15². Yes — it is a right triangle (a 3-4-5 scaling).
Common exam traps
- Hypotenuse is never the shortest side — always identify the right angle first.
- Pythagoras is only for right triangles — for general triangles use cosine rule.
- Units — square both sides in the same unit before adding.
Works well with
- **Hypotenuse calculadora** — same maths, different layout.
- **Triangle area** — ½ × base × height for right triangles.
- **Triangle perimeter** — add all three sides once you know them.
- **Quadratic formula** — distance formula leads to quadratics in harder problems.
Accuracy and sources
We follow BBC Bitesize and exam-board specifications. See editorial policy and corrections. Calculations run in your browser.