# Valley Video charges a $15 annual fee plus $3 per movie for rentals. Last year, Jennifer spent $99 at the store. How many movies did she rent?

##### 1 Answer

Jennifer rented 27 movies.

#### Explanation:

We seek a number of movies

This information models a linear relationship between the number of movies rented (*rate* at which

The equation that we use for a linear model is one like this:

#y=kx+c#

where, in this case,

#y# = total amount spent in a year,#k# = cost per movie rental,#x# = number of movie rentals, and#c# = base fee for the year.

The given information lets us plug in values for three of these four variables, meaning we can solve for the fourth.

#color(white)(XXXX)$99=($3//movie) * x + $15#

#color(white)(XXXX)$84=($3//movie) * x#

#($84)/($3//movie)=x#

#" "27" "movies = x#

And that's our answer.