Respuesta :
Answer:
Jonah has 15 dimes.
Step by step explanation:
Since question 7, tells us that we have to use the following equations to solve the system:
Let x be the nickels
Let y be the dimes
[tex]\begin{gathered} x+y=20\text{ (1)} \\ .05x+.10y=1.75\text{ (2)} \end{gathered}[/tex]We can use the substitution method to solve the system, isolate y in equation (1), and then plug it into equation (2)
[tex]y=20-x\text{ (1)}[/tex][tex]\begin{gathered} .05x+.10(20-x)=1.75 \\ \end{gathered}[/tex]Now, solve for x.
[tex]\begin{gathered} .05x+2-.10x=1.75. \\ -.05x=1.75-2 \\ -.05x=-0.25 \\ x=\frac{-0.25}{-0.05} \\ x=5 \end{gathered}[/tex]That means Jonah has 5 Nickels. Now to solve for y(dimes), substitute x=5 into equation (1)
[tex]\begin{gathered} y=20-x \\ y=20-5 \\ y=15 \end{gathered}[/tex]Jonah has 15 dimes.
