I figured out the equation to solve this:

(1+5.8%)^2(1+x)^3=(1+6.5)^5

But I keep getting the answer wrong. Can someone show me how to do this step by step without using Excel. Thank you

You observe the following yield curve for Treasury securities: Maturity 1 year 2 years 3 years 4 years 5 years Yield 5.5% 5.8% 6.0% 6.3% 65% Assume that the pure expectations hypothesis holds. What is the predicted interest cost if you plan to borrow for 3 years starting 2 year from today