Explanation:
A few hints:
- Angles exactly opposite each other are congruent (the same). It seems that you already know how to use this.
- The angles of an triangle add up to 180 degrees. You could apply this to #7 and use the above hint to solve for #10.
A straight line is 180 degrees, so a line that separates it into two angles will always add up to 180. you could use this to solve for #8, and use the first hint for #9.
An angle formed by a transversal line and a pair of parallel lines will correspond to each other. Use this to solve #11-18.
I hope this helps!