The answer is -485.
To find this we first need to get rid of the 5 in the denominator.
100 = [tex] \frac{15 - x}{5} [/tex]
So we multiply each side by 5.
500 = 15 - x
Now we need to get rid of the 15. So we subtract 15 from both sides.
485 = -x
Then since our x is negative, we need to divide by -1.
-485 = x
