Ms. Martin was researching the costs of financing $125,000 for a home. She found that the monthly payment for a 6.875% loan for 30 years would be $821.16 per month. She found that the monthly payment for a 6.875% loan for 20 years would be $959.77 per month.

- Write and solve an equation to find the amount of interest she would pay altogether for the 30-year loan.
- Write and solve an equation to find the amount of interest she would pay altogether for the 20-year loan.

Can anyone at least explain how to do this? I'm almost desperate here lol.