posted by help me .
marcy has a total of 100 dimes and quarters. if the total value of the coins is $14.05, how many quarters does she have?
You need two equations to substitute into each other. You need one for the total number of coins, and one for the amount.
d=# of dimes
q=# of quarters
Get how I got those equations? See if you can solve the rest. If you can't, post again, and I'll see if I can help you.