Pythagorean Theorem Calculator › Legs 3 and 12

Hypotenuse of 3 and 12

Hypotenuse = √153 ≈ 12.369317

For a right triangle with legs 3 and 12, the hypotenuse c satisfies a² + b² = c²:

3² + 12² = 9 + 144 = 153, so c = √153 ≈ 12.369317 (3√17).

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Other triangles with leg 3

3 & 1 · 3 & 2 · 3 & 3 · 3 & 4 · 3 & 5 · 3 & 6 · 3 & 7 · 3 & 8 · 3 & 9 · 3 & 10 · 3 & 11

Frequently asked questions

What is the hypotenuse of a triangle with legs 3 and 12?

It is √153 ≈ 12.369317 (or 3√17 in simplified radical form). Using a² + b² = c²: 3² + 12² = 153.

Is 3, 12, … a Pythagorean triple?

No. The hypotenuse √153 is not a whole number, so 3 and 12 do not form a Pythagorean triple with an integer hypotenuse.