geometry · worked example

Solve right triangle with legs 5 and 12

Method: Pythagorean theorem. Verified step-by-step solution with our free AI math solver.
Problem

a2+b2=c2, a=5, b=12a^2 + b^2 = c^2,\ a=5,\ b=12

Step-by-step solution

  1. Identify the legs: a=5a = 5, b=12b = 12.

  2. Apply Pythagorean theorem: a2+b2=c2a^2 + b^2 = c^2.

  3. Substitute: 25+144=c225 + 144 = c^2, so c2=169c^2 = 169.

  4. Take positive square root: c=13c = 13.

  5. (5,12,13)(5, 12, 13) is the second-smallest primitive Pythagorean triple (one not generated by scaling another) — appears constantly in test problems.

Answer

c=13c = 13

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