I'm assuming that you're meaning to write the following:
In this case, we compare similar bases' exponents. We subtract the lesser from the higher number and keep the rest wherever the higher number is.
More generally, if we have xn/xm, it would simplify to xn-m. You can see that in the case where m>n (n-m would be negative), then xn-m would be written as 1/(xm-n), if we want to keep positive exponents.
ANYWAY, in our case,
Let's first notice that 36/12 is equal to 3 = 3/1.
Now, using our exponent rule from above, we can see that we have an m and n in the numerator, and m in the denominator. Since m is the only one in common, that's the only one we need to worry about simplifying. The 5 on top is bigger than 3 on the bottom, so we know that m is going to end up on top. 5-3=2, so we have 2 m's left over on top.
Our answer would be: