2(n-9) = 3(n + 5)
2n - 18 = 3n + 15
2n - 3n = 15 + 18
-n = 33
n = -33
If you would like to solve a^(-5)b^(-4) / a^(-13)b^8, you can do this using the following steps:
a^(-5)b^(-4) / a^(-13)b^8 = a^13 / a^5b^4b^8 = a^8 / b^12
The correct result would be c. a^8 / b^12.
4/6 = 1/x cross multiple so x= 1.5 dollars