Corresponding Angles

When two lines are crossed by another line (called the Transversal):

The angles in matching corners are called Corresponding Angles.

corresponding angles

 

 

In this example a and e are corresponding angles

 

Also:
b and f are corresponding angles
c and g are corresponding angles
d and h are corresponding angles

Parallel Lines

When the two lines being crossed are Parallel Lines the Corresponding Angles are equal.

images/parallel-pair.js

(Click on "Corresponding Angles" to have them highlighted for you.)

 

2117,2118