Angles in parallel lines

Maths

Alternate exterior angles sum to 180 degrees.

If I know Angle A and Angle B are allied angles and Angle A = 60 degrees, what is Angle B?

An intersection is the point at which two lines never meet.

Angles on a straight line sum to 180 degrees.

Angles around a point sum to 180 degrees.

If a straight line contains 2 angles, one of which is 54 degrees, what is the size of the other angle?

If a + b = 180 degrees, then 2a + 2b = 360

Vertically opposite angles are never equal.