# Exterior angles formed by Nonparallel lines and their Transversal

Externally, some angles are formed geometrically when two or more nonparallel lines are intersected by their transversal line and the outer angles are called as exterior angles of nonparallel lines and their transversal.

Look at the picture which expresses intersection of two nonparallel lines and their transversal. In this case, four angles are formed externally and they are called as exterior angles of nonparallel lines and their transversal line.

## Exterior angles

When two nonparallel lines are cut by their transversal, four exterior angles are formed possibly in geometric system.

$1. \,\,\,\,\,\,$ $\angle APX$ is first external angle

$2. \,\,\,\,\,\,$ $\angle XPB$ is second external angle

$3. \,\,\,\,\,\,$ $\angle DQY$ is third external angle

$4. \,\,\,\,\,\,$ $\angle YQC$ is fourth external angle

The four angles are formed externally. So, they are known as exterior angles of nonparallel lines and their transversal.

### Property

All exterior angles are not equal when two nonparallel lines are cut by their transversal line. It is due to the non-parallelism of the intersecting lines.

Email subscription
Math Doubts is a free math tutor for helping students to learn mathematics online from basics to advanced scientific level for teachers to improve their teaching skill and for researchers to share their research projects. Know more
Follow us on Social Media
###### Math Problems

Learn how to solve easy to difficult mathematics problems of all topics in various methods with step by step process and also maths questions for practising.