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Triangle from three sides

Find area and all angles from three side lengths.

How this works

Heron’s formula gives area; the law of cosines gives each opposite angle.

Example

Using the example inputs, area (square units) is 6.

A (units)
3
B (units)
4
C (units)
5
Area (square units)
6

Scope and assumptions

Uses your inputs only; results are rounded for display.

OpenStax mathematics

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