Find the hypotenuse of a right triangle from the two perpendicular side lengths.
Right triangles, areas, slopes, distances and common coordinate-geometry formulas.
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Sides 3 and 4 produce a hypotenuse of 5.
Find the hypotenuse of a right triangle from the two perpendicular side lengths. It is designed for quick estimates and everyday problem solving. When a calculation affects a contract, tax filing, medical decision or other high-stakes situation, verify the result with the appropriate professional or authoritative source.
For perpendicular legs 5 and 12, the hypotenuse is √(5² + 12²) = √169 = 13. The hypotenuse is the longest side and sits opposite the 90-degree angle.
Do not misuse this formula: a² + b² = c² applies to a right triangle only. For an arbitrary triangle, use the law of cosines with the included angle instead.
Find the hypotenuse of a right triangle from the two perpendicular side lengths.
c = √(a² + b²).
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