How it works
Match a side with its opposite angle. With a = 5, A = 30° and B = 90°, side b is 10 and C is 60°. Both known angles must be positive and their sum must be below 180°. This form uses two known angles, avoiding the ambiguous two-sides-and-one-angle case.
Inputs and units
| Input | Example value | What to enter |
|---|---|---|
| Side a opposite angle A | 5 | Enter a numeric value. Must be greater than zero. |
| Angle A | 30 ° | Required unit: °. Must be greater than zero. Allowed range: 0.000001–179.999999. |
| Angle B | 90 ° | Required unit: °. Must be greater than zero. Allowed range: 0.000001–179.999999. |
Worked example
Show example inputs and results
This example is generated by the same calculation engine using the starting values in the form. Your own inputs produce your own result.
- Side a opposite angle A
- 5
- Angle A
- 30 °
- Angle B
- 90 °
Complete example results
- Side b
- 10
- Side c
- 8.66025404
- Remaining angle C
- 60 °
Reading the result
Enter lengths in the same unit. Area uses the square of that unit and volume its cube. Height is perpendicular to the base; use a sloping side only when the input explicitly asks for it.
Questions and answers
Can I use the example values for my own calculation?
The example values illustrate the calculation. Replace every input with your own information, especially dates, rates and the selected operation.
Which unit do the returned sides use?
They use the same length unit as side a. Angle entries are degrees; converting a radian measurement is a separate step.
Why are some results rounded?
Results display up to 8 decimal places. Calculations use the unrounded values; very small values use scientific notation. JavaScript floating-point arithmetic can introduce tiny rounding differences.
Are my inputs sent to a server?
The calculator processes inputs in your browser. Its code does not send your values to a server.
Method sources: openstax.org