Learn the steps for finding the missing angle in geometry problems by using the angle addition postulate. This tutorial ...

Interior angles in a triangle add up to 180˚. Triangles close triangleA polygon with three straight sides. have three sides, therefore they have three angles. Interior angles in a triangle sum to a ...

A complete lesson on the interior angle sum of a quadrilateral. Requires pupils to know the interior angle sum of a triangle, and also know the angle properties of different quadrilaterals. A nice ...

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. What is a quadrilateral? A quadrilateral is a four-sided shape where each of the sides are straight and ...

Circles have different angle properties, described by a number of theorems. This is one of two guides on circle theorems, with this guide covering the following: the angle subtended by an arc at the ...