Answer:
Given that,
Julie gets a prepaid cell phone. Initially she has a $40.00 balance on the phone.
Each minute of talking cost $0.15.
To find the value of x that makes f(x)=0.
Let x be the number of munites of talking.
we know that each minute of talking cost $0.15,
we get the equation as,
[tex]f(x)=40-0.15x[/tex]To find the value of x when f(x)=0,
Substitute f(x)=0, we get
[tex]40-0.15x=0[/tex][tex]0.15x=40[/tex][tex]x=\frac{40}{0.15}[/tex][tex]x=266.67[/tex]Answer is: x=266.67
It means that with $40.00 balance, Julie can speak upto 266.67 minutes.
