Triangle from three sides
a, b, c → angles, area, perimeter (Heron's formula)
Sides
Existence check: the sum of any two sides > the third. Angles via the law of cosines: cos A = (b²+c²−a²)/2bc. Area via Heron: √(s(s−a)(s−b)(s−c)). The largest angle is opposite the largest side.
Solution
- ∠A
- 36.87°
- ∠B
- 53.13°
- ∠C
- 90°
- Area
- 6
- Perimeter
- 12
Right triangle ✓