I'll give you an example of a similar problem - that way you can see how it's done and then apply the same technique to this problem.
Suppse you have:
Its inverse is found by getting the x variable all by itself:
1. Subtract 10 from both side:
2. Divide both sides by -3:
3. Now take the natural log of both sides:
4. Since
, this means:
5. Divide by -2:
So now if you are given a value for y, you can determine the corresponding value of x. For example - suppose y = 4; then:
Hope this helps - can you apply this same technique to your problem?