Law of Sines
Solve a triangle from two angles and the side opposite the first.
Your numbers
Side opposite B
Use consistent units. The result follows the assumptions you enter.
Scenario comparison
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Formula
Use a/sin(A) = b/sin(B) = c/sin(C) and C = 180°−A−B. Each lowercase side is opposite its matching uppercase angle. Input angles are in degrees and side lengths share a unit.
Solve a triangle from two angles and the side opposite the first.
Worked example
- Side opposite A (m)
- 5
- Angle A (degrees)
- 30
- Angle B (degrees)
- 60
- Side opposite B
- 8.66025403784 m
- Side opposite C
- 10 m
- Angle C
- 90 °
Scope and limitations
Use consistent units. The result follows the assumptions you enter.
Inputs are checked for missing values and allowed ranges. A result outside the finite numeric range is not displayed. Rounding affects display, while the calculation uses the model’s numeric precision.
Check your units and assumptions before relying on a result. Changing a label does not convert a currency or physical unit.
Formula version: f13443b28788 · Example checked: