Pythagorean theorem
Enter any two sides of a right triangle and the calculator solves for the third side and triangle area.
Open calculatorTriangle area (Heron’s formula)
Semi-perimeter s = (a + b + c) / 2; Area = √[s(s − a)(s − b)(s − c)]. The three lengths must satisfy the strict triangle inequality (any two sides summed must exceed the third).
Triangle area
6
Semi-perimeter (s)
6
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A 3–4–5 right triangle has an area of exactly 6.
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