What this calculator does
Law of sines (solve a triangle) works out finds the remaining sides and angles from two angles and one side. Enter your own figures above and the answer updates as you type: nothing is fixed in the code, so the result reflects exactly the numbers you supply.
The formula this calculator evaluates is printed under the tool and explained below, so you can check the working by hand or reuse it in a spreadsheet.
The formula
Formulaa/sin A = b/sin B = c/sin C
The inputs explained
| Field | What to enter |
|---|---|
| Angle A (°) | A number, measured in °. Starts at 50. |
| Angle B (°) | A number, measured in °. Starts at 60. |
| Side a (opposite angle A) | A number. Starts at 10. |
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How the answer changes with angle a
Every other input is held at the calculator’s starting values while angle a varies. Select any row to load that scenario into the calculator.