Question

Dianne knows a phone call a friend for the first 3 minutes costs 25 cents and 10 cents for each additional minute

Answer 1

Question:

Diane knows a phone call to a friend costs .25 for the first three minutes and .10 for each additional minute. Let y be the cost of a call that lasts x minutes. Write the slope and an equation relating x and y.

Answer:

Slope  =  0.10 or  $\frac{1}{10}$

Equation relating x and y is y =  0.10x- 0.05

Step-by-step explanation:

Given:

Cost for first three minutes  = 0.25 cents

Cost for each additional minute = 0.10 cents

To Find:

The slope and an equation relating x and y = ?

Solution:

Let y be the cost of a call that lasts x minutes

Then,

y = 0.25 + 0.10(x-3)

y = 0.25 + 0.10x- 0.30

y =  0.10x- 0.05-------------------(1)

In the equation

y = mx +b------------------------------(2)

m is the slope

Comparing eq(1) and(2)]

m =0.10 or  $\frac{1}{10}$