5) Angle 1 = 140 degrees.
When two parallel lines are cut across by a transversal, there will be a pair of corresponding angles which are equal.
6) Corresponding angles.
7) We have another case of corresponding and alternate angles.

8) y = 112 degrees. | Both are alternate angles
9) 72 degrees and x are supplementary (adds up to 180 degrees)

10) x and (5y - 3) are corresponding angles and are therefore equal.
