We have
.
To find inverse function
we substitute x with
and vice-versa to get

Now solve for
. Note that I will use
instead.

So we find that
.
Hope this helps.
When two fractions have the same denominator, you can compare which fraction is greater by just comparing the numerators.
For example, if you have 2/5 and 3/5, the denominators are the same. So you can just look at the numerators. 3 is greater than 5, so 3/5 is greater than 2/5.
The reasoning to this is that the two numbers are divided by the same number (5), so you can compare the original numbers (numerators).
Basically, we need to find the lowest common multiple of 6 and 9....and that would be 18.
so 18 minutes from 4 p.m. is 4:18 p.m. <===
58 should be the answer for the perimeter