Corresponding Angles

Parallel lines occur a lot in life. Can you see any around you?

A transversal is the name we give to a line that cuts across a pair of parallel lines, like a road crossing a railway track.

When a transversal crosses a pair of parallel lines, it forms pairs of corresponding angles. These are always equal. Let’s see them on a diagram.

Worked Example

Exercise 1

Alternate angles

As well as creating corresponding angles, a transversal crossing parallel lines also forms alternate angles. Let’s draw some diagrams to identify these.

In general the most important thing is that we know when two angles are equal, but we should also know why (i.e. if it is because they are corresponding, alternate, or vertically opposite) and we can also be tested to check that we know these classifications.

Exercise 2

Answers