Right Triangle Calculator
Solve a right triangle from any two values — two sides, or one side and one acute angle.
Sides
a = 3, b = 4, c = 5
- Angles
- α = 36.86989765°, β = 53.13010235°, 90°
- Area
- 6
- Perimeter
- 12
- Height to the hypotenuse
- 2.4
Show the work
Hypotenuse from Pythagoras
c = √(a to the power of 2 + b to the power of 2)
√(3 to the power of 2 + 4 to the power of 2) = 5
Angles: α from the legs, β = 90° − α
α = arctan(a ÷ b)
arctan(3 ÷ 4) = α = 36.86989765°, β = 53.13010235°
Solved: the three sides
check: a to the power of 2 + b to the power of 2 = 3 to the power of 2 + 4 to the power of 2 = 5 to the power of 2 = c to the power of 2
a = 3, b = 4, c = 5
How it works
a² + b² = c²; sin α = a ÷ c; cos α = b ÷ c; tan α = a ÷ b; α + β = 90°
Questions
- How does the right triangle calculator work?
- a² + b² = c²; sin α = a ÷ c; cos α = b ÷ c; tan α = a ÷ b; α + β = 90°.
- What do I need to enter?
- Leg a, Leg b, Hypotenuse c, Angle α (opposite a), Angle β (opposite b), Units. Optional fields can be left blank.
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