Geometry Basic

Pythagorean Theorem — a² + b² = c²

Find the hypotenuse, a missing leg, or verify whether three sides form a right triangle. Visual diagram shows the squares built on each side.

Find hypotenuse or leg

Right/acute/obtuse classification

Squares diagram

Input

Mode

Leg a

Leg b

Try:

Hypotenuse c

Known leg b

Try:

Side a

Side b

Side c (longest)

Try:

Result

Select mode and enter values.

Step-by-Step Solution

Right Triangle with Squares

The Theorem

a² + b² = c²

In any right triangle, the square of the hypotenuse equals the sum of the squares of the legs. The hypotenuse is always the longest side, opposite the right angle.

Rearranging: c = √(a²+b²), a = √(c²−b²)

Triangle Classification

a²+b² = c² → Right triangle
a²+b² > c² → Acute triangle
a²+b² < c² → Obtuse triangle

Common Pythagorean triples: 3-4-5, 5-12-13, 8-15-17, 7-24-25.

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