Triangle Calculator
Calculate triangle properties: area, perimeter, angles, and sides
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Triangle Formulas
Area (Base + Height)
A = ½ × b × h
Where b is the base and h is the height perpendicular to it.
Heron's Formula
A = √[s(s-a)(s-b)(s-c)]
Where s = (a + b + c) / 2 is the semi-perimeter.
Law of Cosines
c² = a² + b² - 2ab×cos(C)
Used to find the third side when two sides and the included angle are known.