The value of n is a distance of 1.5 units from -2 on a number line. Click on the number line to show possible values on n. (Please answer this to me in a simple way and explain, I also don't understand how 1.5 - -2 is 0.5 or 3.5, I'm very confused)

Ricky takes out a $31,800 student loan to pay his expenses while he is in college. after graduation, he will begin making payments of $190.66 per month for the next 30 years to pay off the loan. how much more will ricky end up paying for the loan than the original value of $31,800? ricky will end up paying $ more than he borrowed to pay off the loan.