Eighths and their multiples are common fractions which I recommend memorizing, but to actually solve this, you use the literal meaning of a fraction and divide 5 by 8. See the long-division below (it was surprisingly difficult to type, so I hope it helps!).
To round 0.625 to the nearest hundredth, we go to the second decimal place, which is 5, so we round up to 0.63.
100% - x
115% - 84.87
x=(100*84.87)/115=73.8


We could solve for 'x' in the 2nd equation and then plug that into the first equation for 'x' and solve for 'y':

Subtract 6y to both sides:

Divide -2 to both sides:

Plug in 3y + 17 for 'x' in the first equation:


Distribute 5:

Combine like terms:

Subtract 85 to both sides:

Divide 17 to both sides:

This is the y-coordinate of the solution.
See picture for solution steps and answer.