How to Calculate Law of Sines
What is Law of Sines?
The Law of Sines states that in any triangle, each side divided by the sine of its opposite angle is constant. It is used to solve triangles when you know an angle-side pair plus another angle or side.
Step-by-Step Guide
- 1The ratio a/sin(A) = b/sin(B) = c/sin(C)
- 2Use when given: AAS, ASA, or SSA (be careful — SSA can give 0, 1, or 2 solutions)
Worked Examples
Input
A=30°, B=45°, a=10
Result
b ≈ 14.14
10/sin30° = b/sin45° → b=10√2
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