I need help find the three equations out of this:

I should be able to use system of equations or matrices to do this, but I'm not able to pull out the equations. Any help?Code:A piggy bank contains 50 coins, all of them nickels, dimes, or quarters. The total value of coins is $5.60 and the value of the dimes is five times the value of the nickels. How many of each type are there?