A = y(9 + 3x) factor y out of 9y+3yx, then devided both sides by (9+3x)
A/(9+3x) = y
Answer: -1.409, -1.48, 0.007 , 0.10, 0.17
Hope this helps
The tip would be $17.26
All you have to do is multiply 86.29 x .2 (20%)
I need a picture of the problem or something at least