x = dimes
y = quarters
We also know:
Dimes: 0.10
Quarters: 0.25
100 = x + y
So, 0.10x + 0.25y = 100
And, y = 100 - x
Let’s use substitution:
0.10x + 0.25( 100 - x ) = 100
= 0.10x + 25 - 0.25x = 100
= 25 - 100 = 0.25x - 0.10x
= (-75) = 0.15x
x = (-75) divide by 0.15
x = (-500)
