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unit of measure: the base unit | the supplementary unit | the derived unit

geometry: the area of a flat figure | the area of a solid | the volume of the solid

The area of a triangle

by Heron’s formula


A triangle is a polygon formed by the union of three segments, where the points of intersection are non-collinear points. Points of intersection are called vertexes, and the segments are referred to as sides.

The scalene triangle is the triangle which has all sides of different lengths.

The area of a triangle, by using Heron’s formula, is equal to the radical of differences of semi-perimeter of a triangle and each side of it.

Computing relationship:



a, b, c — the sides of triangle.

Calculator: the area of a triangle

For separation of number integers and decimals, use the symbol – point [.]

the side of triangle — a

the side of triangle — b

the side of triangle — c


the area of a triangle =



context information: contemporary and archaic unit of measurement of area