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Right triangle calculator

Hypotenuse = √(leg one² + leg two²). Area = leg one × leg two ÷ 2.

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Answer

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Hypotenuse = √(leg one² + leg two²). Area = leg one × leg two ÷ 2.

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Precision and calculation record
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    Formula and assumptions
    The entered legs must meet at a right angle and use the same units. The reported acute angle is opposite the first leg.
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    Updated 
    Using Right triangle calculator
    Hypotenuse = √(leg one² + leg two²). Area = leg one × leg two ÷ 2.
    The entered legs must meet at a right angle and use the same units. The reported acute angle is opposite the first leg.
    Next: Triangle area calculator
    A worked example
    With first perpendicular leg = 3, second perpendicular leg = 4, the hypotenuse is 5.
    Next: Trapezoid area calculator
    Before you use the result
    The entered legs must meet at a right angle and use the same units. The reported acute angle is opposite the first leg.
    Example results for first perpendicular leg
    These examples use Second perpendicular leg: 4. They are reference calculations, not recommended settings.
    First perpendicular legHypotenuse
    1.54.27200187266
    35
    67.21110255093
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    ToolOctopus. “Right triangle calculator.” Updated 2026-09-26. https://tooloctopus.com/right-triangle-calculator.
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