Question

The following graph represents the cost of a phone plan after a certain number of text messages used in a month. Analyze the graph to answer the following questions. (I included a picture of the graph)
(a) How much would you have to pay if you used:
500 text messages_______________
1800 text messages_______________

(b) Interpret f(1400) = 60

(c) What might have caused the graph to begin increasing at 800 text messages?

Answer 1

Here we want to analyze the given graph.

The answers are:

a) for 500 messages the cost is $30 and for 1800 messages the cost is $80.

b) It means that for 1400 messages the cost is $60.

c) Because there is a fixed cost for the first 800 messages.

Let's expand more on each solution.

First, remember that the horizontal axis represents the number of text messages end in hundreds, while the vertical axis represents the cost in dollars.

a) We want to find the cost for 500 texts and 1800 texts.

To find the cost for 500 texts, you need to count 5 squares on the horizontal axis, and then see where the graph intersects the vertical axis for that value.

We can see that:

f(500) = $30

We do the same for 1800 (this time you count 18 squares), then we get:

f(1800) = $80

b) f(1400) = 60

This would mean that the cost of 1400 text messages is 60 dollars.

c) Assume that for the first 800 text messages you have a fixed cost, and after that the company starts to charge an extra for each message you send, this is why we would have a linear increase after the message number 800.

If you want to learn more, you can read:

brainly.com/question/11252591