Solve for x.

10000 = 2500(1.0425)^3 + X(1.0425)^2 + 3500(1.0425)^1

what is the present value of annuity of $950 per year for 18 years ( with the first payment to be made today and the last payment to be made 17 years from today) give an interest rate of 7.5% p.a?