Angle chasing

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Angle chasing is a technique to solve or help in solving a kind of geometric problems by studying the angles first. It is often advisable to start geometrical problem-solving with angle-chasing as it's a simple way to get further information about the problem.

Contents 1 Angle chasing stages 1.1 Supplementary angles 1.2 Sum of the angles in triangles and quadrilaterals 1.3 Uses for circumferences

[edit] Angle chasing stages

[edit] Supplementary angles

Supplementary -those that make up a straight line- can be found quickly.

[edit] Sum of the angles in triangles and quadrilaterals

In every polygon the sum of the external angles is always 360°. There is a nice formula for the internal angle sum.

[edit] Uses for circumferences

Two different triangles having one side in common have all vertices on just one circle if their angles opposite the common sides are equal.