Melanie has $1.80 worth of nickels and dimes. She has 12 more nickels than dimes. Graphically solve a system of equations in order to determine the number of nickels, x , x, and the number of dimes, y , y, that Melanie has.

You just purchased two coins at a price of $670 each. because one of the coins is more collectible, you believe that its value will increase at a rate of 7.1 percent per year, while you believe the second coin will only increase at 6.5 percent per year. if you are correct, how much more will the first coin be worth in 15 years?