The usual formula for finding the amount A of a monthly payment on principal amount P with annual interest rate r over t years is
... A = Pr/(12·(1 -(1+r/12)^(-12t)))
Filling in P=1000, r=.075, t=2, you get
... A = 45.00
The montly payment is $45.00.
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The given formula looks nothing like one used to compute the payment, nor is it anything like a formula used to compute interest on such a loan. We cannot figure out how to use it (or if it is even applicable) without knowing the definitions of the variables involved.
