Right Triangle Solver
Given any 2 of (a, b, c, angle), solve all remaining sides + angles.
Result
Sides
a=3.000, b=4.000, c=5.000
Angles: A=36.87°, B=53.13°, C=90°.
- a (opp A)3.000000
- b (opp B)4.000000
- c (hypotenuse)5.000000
- Angle A36.8699°
- Angle B53.1301°
- Angle C90°
- Area6.000000
- Perimeter12.000000
Step-by-step
- Mode: ab → solve right triangle.
- a = 3.0000, b = 4.0000, c = 5.0000.
- Angle A = arctan(a/b) = 36.8699°.
How to use this calculator
- Pick what's given.
- Enter the two known values.
- Read all sides and angles.
About this calculator
A right triangle has one 90° angle (C). Given any 2 pieces of (a, b, c, angle A), the remaining 2 are determined. Common cases: SOHCAHTOA — sin(A) = opposite/hypotenuse = a/c; cos(A) = b/c; tan(A) = a/b. Pythagoras: a² + b² = c². The simplest right triangle math case that students see; foundation for surveying and 3D vector decomposition.
Frequently asked
Mnemonic for trig ratios in right triangles. SOH: Sin = Opp/Hyp. CAH: Cos = Adj/Hyp. TOA: Tan = Opp/Adj.
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