Y=7/9x-7 is it parallel, perpendicular, or neither

y = 7/9x - 7 
y = -7/9x - 7 

They do not have the same m. They won't be parallel. Now check for perpendicularity. 

The first has a slope of 7/9. That means the next has to have a slope of the negative reciprocal of the first. So, is -7/9 the negative reciprocal of the first? No. It is negative, but the reciprocal would be 1 / (7/9) = 9/7 

That should be enough so you can clear the rest without me explaining them. I'll just put the answers down: 

The answer is part a: use