Geometry Angles Post 5

Vertically Opposite Angles
These are pretty logical - once you've seen them once you'll be sweet with these.  Because they look as they are.

Vertically Opposite Angles - are created when two straight lines cross over.  They are the angle exactly opposite each other. 

Here a and b a vertically opposite angles.  The rule is "vertically opposite angles are equal". 

These problems can be found on page 220 exercise 14.9 - go answers only.