# Line & angle proofs

Explore different ways of proving some theorems about lines and angles. Some transformations are used.

### Problem

and are parallel.
The interior angles of a quadrilateral sum to 360, degree.
Complete the equations to prove that corresponding angles always have equal measure.
start color pink, b, end color pink, equals
start color purple, c, end color purple, equals
start color purple, c, end color purple, equals