Haley owes 25 dollar, and every week she save $4.50 to pay her so we are going to name our variables like this:
y = money owed
x = number of weeks
and we can write the model like:
![y=4.5(x)+25](https://img.qammunity.org/2023/formulas/mathematics/college/2of06byc2fwcbwr6kdhwtgv9xhfa9694u0.png)
For example, in the week 0 x = 0 and y is going to be equal to 25 that is the initial debt
And for knowing when she is going to be able to pay the debt we rplace y for 0
![0=-4.5(x)+25](https://img.qammunity.org/2023/formulas/mathematics/college/zozydhigz2a007j1iwrtv82flu0v58r00x.png)
and we solve for x
![x=(25)/(4.5)=5.5](https://img.qammunity.org/2023/formulas/mathematics/college/xrkf787w4qihv0t761t8t88ove5wmlcghw.png)
So in 5 weeks and a half she is going to finish paying the debt