Answer:
5 quarters
Step-by-step explanation:
x = number of quarters
17 - x = number of half dollars {there are 17 total coins}
0.25x + 0.5(17 - x) = 7.25 {value of coin times number of coins equals total value}
0.25x + 8.5 - 0.5x = 7.25 {used distributive property}
-0.25x + 8.5 = 7.25 {combined like terms}
-0.25x = -1.25 {subtracted 8.5 from each side}
x = 5 quarters {divided each side by -0.25}
17 - x = 12 half dollars {substituted 5, in for x, into 17 - x}
5 quarters
