Answer:
x = 5
Step-by-step explanation:
15 - 10 = x
Funny, this looks like a complex graph, until you realize that the numerator can be written like (x+3)(x-9).
So really, this is a straight line f(x) = x-9.
But wait, there's a catch. x≠3, because that would divide by zero. So in your straight line, you have to draw a "hole" at (3,6)
D, because the sum is no more than 28 so it could be equal or less than.