Let's write two equations that represent the allowance of each person.
Kara's Plan.
She will get 1 more dollar each day, starting with 3 dollars:
[tex]y=x+3\begin{cases}x=days \\ y=dollars\end{cases}[/tex]
Kevin's Plan.
He will get double money each day, starting with 0.25 dollars.
[tex]z=(2^{x-1})\cdot(0.25)\begin{cases}x=days \\ z=dollars\end{cases}[/tex]
In order to get how much money Kara gets, one can substitute the number of days into 'x'.
[tex]\begin{gathered} x\rightarrow y \\ 1\rightarrow4 \\ 2\rightarrow5 \\ 3\rightarrow6 \\ 4\rightarrow7 \\ 5\rightarrow8 \end{gathered}[/tex]
