What is a Hypotenuse?
Learn the definition of a hypotenuse. It is the longest side of a right-angled triangle, always located directly opposite the 90-degree right angle.
In geometry, a hypotenuse is the longest side of a right-angled triangle. Its defining characteristic is that it is always positioned directly opposite the 90-degree right angle.
The length of the hypotenuse can be found using the Pythagorean theorem, which states that the square of the hypotenuse is equal to the sum of the squares of the other two legs (a2 + b2 = c2).
If you know the lengths of the two shorter legs, you can instantly find the hypotenuse using our Right Angle Calculator Triangle.
The term originates from the Greek word hypoteinousa, meaning "stretching under" (as in a line stretched under a right angle). It is a critical concept for determining diagonal distances in construction, roofing, and spatial navigation.
Right Angle Calculator Triangle
Apply the concepts from this glossary using our free interactive calculator.
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