Question 410157
"Joe has a collection of nickles and dimes that is worth $8.55" ___ 5n + 10d = 855


" If the number of dimes is tripled and the number of nickles is decreased by 2, the value of the coins would be $23.45"
___ 5(n-2) + 10(3d) = 2345


5n - 10 + 30d = 2345


5n + 30d = 2355


subtracting 1st equation ___ 5n + 30d - (5n + 10d) = 2355 - (855)


20d = 1500


solve for d and substitute the value into any of the equations to find n