By sides: equilateral (all equal), isosceles (two equal), scalene (all different). By angles: acute (all below 90°), right (one at 90°), obtuse (one above 90°). All interior angles sum to 180°.
a/sin(A) = b/sin(B) = c/sin(C). Used when you know two angles and a side (AAS/ASA) or two sides and a non-included angle (SSA).
c² = a² + b² − 2ab·cos(C). Used when you know two sides and the included angle (SAS) or all three sides (SSS). For right triangles it reduces to the Pythagorean theorem.
Area = ½ × base × height. When height is unknown use Heron's formula: √(s(s−a)(s−b)(s−c)) where s = (a+b+c)/2. Or use Area = ½ × a × b × sin(C).
It supports SSS, SAS, ASA, AAS, and SSA configurations and returns all missing sides, angles, area, and perimeter.
By sides: equilateral (all equal), isosceles (two equal), scalene (all different). By angles: acute (all below 90 degrees), right (one at 90 degrees), obtuse (one above 90 degrees). All interior angles sum to 180 degrees.
a/sin(A) = b/sin(B) = c/sin(C), used when you know two angles and a side (AAS/ASA) or two sides and a non-included angle (SSA).
c^2 = a^2 + b^2 - 2ab*cos(C), used when you know two sides and the included angle (SAS) or all three sides (SSS). For right triangles it reduces to the Pythagorean theorem.
When height is unknown, Heron's formula is used: the square root of s(s-a)(s-b)(s-c), where s = (a+b+c)/2. Alternatively, Area = 1/2 x a x b x sin(C).