Area of a triangle.

The area $A$ of a triangle with base $b$ and height $h$ is given by $A = \frac{1}{2} b h.$ The base can be any side, and the height is the perpendicular distance from that side to the opposite vertex.

Important properties

• Area is always a positive number.

• Any side can be chosen as the base, as long as the corresponding height is used.

• If the triangle's vertices are known, other formulas (like Heron's formula or using coordinates) can be used.