Question 152485
let d=dimes, n=nickels


"Joe has a collection of nickels and dimes that is worth $5.65" __ 10d+5n=565


"If the number of dimes were doubled and the number of nickels were increased by 8, the value of the coins would be $10.45"
__ 10(2d)+5(n+8)=1045 __ 20d+5n+40=1045 __ 20d+5n=1005


subtracting equations __ (20d+5n)-(10d+5n)=1005-565 __ 10d=440 __ d=44