Answer:
9x+9
Step-by-step explanation
Combine like terms (6x and 3x, 2 and 7)
Well I would solve it but where's the problem?
Answer:
11) 0.6
12) The maximum height of the ball was 2[ seconds] after it was thrown (I am assuming because the answers are cut off a bit.)
13) $2.50
14) (2,-15)
15) I don't know, since I can't see all the graphs and options. But I want to say the sideways parabola, or the only one shown in the image given