Question

A phone company offers two monthly plans. Plan A costs $25 plus an additional $0.09 for each minute of calls. Plan B has no initial fee but costs $0.14 for each
minute of calls.
For what amount of calling do the two plans cost the
same?
minute
E

Answer 1

Using linear functions, it is found that the two plans cost the same for 5000 minutes of calling.

What is a linear function?

A linear function is modeled by:

$y = mx + b$

In which:

• m is the slope, which is the rate of change, that is, by how much y changes when x changes by 1.

• b is the y-intercept, which is the value of y when x = 0.

For Plan A, the cost is of $25 plus an additional $0.09 for each minute of calls, hence the y-intercept is $b = 25$, the slope is of $a = 0.09$, and the function is:

$A(x) = 0.09x + 25$

For Plan B, the cost is of $0.14 for each minute of calls, hence the y-intercept is $b = 0$, the slope is of $a = 0.14$, and the function is:

$B(x) = 0.14x$

The plans cost the same for x minutes of calling, considering that:

$B(x) = A(x)$

$0.14x = 0.09x + 25$

$0.05x = 250$

$x = \frac{250}{0.05}$

$x = 5000$

The two plans cost the same for 5000 minutes of calling.

To learn more about linear functions, you can take a look at brainly.com/question/24808124