Finding the measures of angles and classifying relationship help!?

I forgot how to do this and I left my math book at school so I need help with this problem :/

Using complete sentences, classify the relationship between ∠7 and ∠8 created by the intersection of lines C and D.
Use complete sentences to explain how the special angles created by the intersection of lines C and D can be used to solve for y.
Solve for y and find the measures of ∠7 and ∠8