Scalene Triangle Calculator

Enter three sides of a scalene triangle to find all angles, area, perimeter, and more with step-by-step solutions.

Enter Three Sides

Result

Area (Heron's Formula)
--
square units
Side a--
Side b--
Side c--
Angle A--
Angle B--
Angle C--
Perimeter--
Semi-perimeter (s)--
Type--

Step-by-Step Solution

What is a Scalene Triangle?

A scalene triangle is a triangle in which all three sides have different lengths, and consequently all three angles have different measures. This is in contrast to isosceles triangles (two equal sides) and equilateral triangles (all sides equal).

Formulas Used

Heron's Formula

Compute area from three sides using the semi-perimeter.

A = sqrt(s(s-a)(s-b)(s-c))

Law of Cosines

Find each angle from the three known sides.

cos(A) = (b^2+c^2-a^2)/(2bc)

Triangle Inequality

Sum of any two sides must exceed the third side.

a+b>c, a+c>b, b+c>a

Properties of Scalene Triangles

  • All three sides have different lengths.
  • All three angles have different measures.
  • No line of symmetry exists.
  • The largest angle is opposite the longest side.
  • Can be acute, right, or obtuse depending on angle measures.