You can use scale to solve. 5185/8.5=610
4845/610= about 8 hours.
0 = 230 - 45x
Add 45x to both sides
45x = 230
Divide both sides by 45
x = 230 / 45
Simplify
x = 46 / 9
The solution represents the x intercept, which is where the graph intersects the x axis.
So I did 5/2 and I got 2.5
5 divided by 2 = 2.5
Not 100% sure if I'm right though
So it's 28% so you do 20\28= 15 dollars