yellow [f] key toggles to top row commands printed in yellow.

blue [g] key toggles to front of key commands printed in blue.

PV=Present Value of the Loan Amount

n=number of payments (preceeded by blue [g] will multiply by 12 for monthly payments)

i=interest rate (preceeded by blue [g] will divide by 12 for monthly payments)

PMT=Amount of Payment

FV=Future Value, will give loan balance but does not breakout interest paid versus principle paid.

Assuming a monthly payment the keystrokes are as follows:

50,000 [PV] (do not change [CHS], it's not the cash outflow)

25 [g][12x] (25 years times 12 months)

9 [g][12/] (9% annually divided by 12 months)

[PMT] Solves for payment, the result will be a negative number because this is the cash outflow. Result should be -419.60

To solve for amortization after 5 years, leave the -419.60 in the calculator and press 60 (5 years times 12 months) then [f][AMORT]. Calculator will start flashing "running" then display -21,812.10, that is the amount of interest paid after 60 payments. Press [x>y] the calculator will display -3,363.90, that is the amount of principle paid against the original loan amount. Press the same key [x>y] and it will redisplay the -21,812.10 interest paid.

50,000 (orignal loan amount) - 3,363.90 (principle paid) = 46,636.10 loan balance. It's math, there's usually more than one way to fry a cat.

Good Luck