When faced with 2 parallel lines and a transversal – that is a line that crosses both parallel lines – you automatically end up with a number of angle relationships which you ned to be familiar with. The diagrams below show these relationships.

Alternate Angles (also known as Z-angles)

Corresponding Angles (also known as F-angles)

Co-interior Angles (also known as C-angles)

(R&F) Geometry - Sine & Cosine Rules
(R&F) is it or is it not a Prime Number