Skip to content
Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works

Pythagorean theorem

In a right triangle, the two short sides squared and added equal the long side squared.

The Pythagorean theorem states that for a right triangle with legs a and b and hypotenuse c: a^2+b^2=c^2. It holds for every right triangle and only for right triangles.

Examples

  • Legs 3 and 4 give a hypotenuse of \sqrt{3^2+4^2}=\sqrt{25}=5.

See also

hypotenuse
Read the full section →
Graph settings

Calculator