1. The problem statement, all variables and given/known data We were asked to solve it using Augmented matrix. I just need one more equation though. A jar of coins contains only dimes, nickels, and pennies. There are 98 coins in the jar, and the total value of the coins is $6.49. Set up the system of equations representing this system, in the variables d, n, and p. 2. Relevant equations 1 dime = 10 cents 1 nickel = 5 cents 1 penny = 1 cent 3. The attempt at a solution I set up two equations: d+n+p = 98 10d + 5n + p = 649 but I can't find the third equation. p is a free variable. the 9 in 649 is the clue i think because only nickels and pennies can add up to 9 and there are two possible ways: 1 nickel + 4 pennies, OR 9 pennies So d and n depend on p but I don't know how to express it in an equation. I tried 5n+p=9 but it didn't work. I tried to substitute 5n=9-p for n, but then it's not linear algebra and the answer was not correct.