Finding Interest Rate Using Loan Constant - Iterative Calculation

So I have a created a Data Chart Below. A - C are the columns and 1-7 are the rows. I have hard-coded the equation in cell B5 that I am using.

What I want to do is input an number into B3 that automatically makes Cell B5 equal to Cell C1. Is there a process in excel you can use to do this. Or do you just have to use trial and error?


A B C
1 Loan Amount $10,500,000 0.0730041581143804
2 Term 10 years
3 Rate
4 Amortization 30 years
5 Constant (K) =PMT(B3/12,(B4*12),-1000)*0.012
6 Annual Payment $766,544
7 Monthly Payment $63,879

Example is attached.