Given:
Corey has 2 times as many nickels as dimes
Let the number of nickels = x
Let the number of dimes = y
So,
[tex]x=2y[/tex]and they have a combined value of 80 cents
[tex]5x+10y=80[/tex]Substitute from x = 2y
so,
[tex]\begin{gathered} 5\cdot2y+10y=80 \\ 10y+10y=80 \\ 20y=80 \\ y=\frac{80}{20}=4 \\ x=2y=8 \end{gathered}[/tex]so, the answer wil be:
dimes = 4
nickels = 8