Answer:
The answer to your question is 
Step-by-step explanation:
Here, there is a difference of squares, so just solve it and simplify

Multiply the binomials
= 1 - 
Simplify
= 
= 
I do not understand the context of your question, you need extra information to find this out like a picture or a word problem.
If the angles equal each other you would have to solve for x when angle 7 and 8 equal each other. SO... based on that, x would equal 15. This means measure of angle 7 would equal 45 and measure of angle 8 would equal 45. This may not be true because I have no idea what you are asking
Answer:
B. Zero
Step-by-step explanation:
The slope of the line is in the the first two quadrants and is horizontal, meaning it has zero slope.