Calculate triangle area, perimeter, hypotenuse, angles and more. Supports right triangles (Pythagorean theorem), equilateral, isosceles and scalene triangles.
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In a right triangle: a squared + b squared = c squared. For legs 3 and 4: c = root of (9+16) = 5.
Use Heron's formula: Area = root of s(s-a)(s-b)(s-c), where s = (a+b+c)/2.
All three sides and angles equal (60 degrees each). Area = (root of 3 / 4) x side squared.
By sides: Equilateral, Isosceles, Scalene. By angles: Acute, Right, Obtuse. Angles always sum to 180 degrees.
The sum of any two sides must be greater than the third. 3, 4, 8 is invalid because 3+4=7 < 8.
Sum of all three sides: P = a + b + c.
a/sin(A) = b/sin(B) = c/sin(C). Used when you know two angles and one side.
c squared = a squared + b squared - 2ab x cos(C). Used when you know two sides and the included angle.
