2.25x+8y=100 is the answer to part a
Just expand the terms to get general form.

Hope this helps.
I think it's A. I can't really see the graphs clearly. It's the one that crosses at (15,2)
Answer:
x = -1.3
Step-by-step explanation:
5x +9=2.5
subtract 9 from both sides
5x = -6.6
divide both sides by 5
x=-1.3
Sphere, the answer is a sphere