Corresponding Angles

The diagram shows two parallel lines and a third line (a transversal) crossing them.
If you move A, the direction of the parallel lines changes.
What do you notice about the two angles marked in blue as A moves?

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The two blue angles are called corresponding angles. Each angle has been formed between one of the parallel lines and the tranversal in the same way, so they correspond to each other. These angles are also known as F angles.

Can you find other pairs of angles which correspond to each other?
Use the 'Angle' tool to check that the pairs are equal.
Corresponding angles are equal to each other.

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