Question

How do you make equations for the following problem: A cell phone provider offers a plan that costs $40 per month plus $.20 per text message sent or received. A compared plan costs $60 per month but offers unlimited text messaging.

Answer 1

Let's use y to mean the monthly cost.
For the second plan, what is the monthly cost (using y in an equation)?

Answer 2

$60x

Answer 3

What is x?

Answer 4

Also, where is y?

Answer 5

Thts the problem I'm having idk if x should b monthly cost or texts

Answer 6

Here is the second plan:
"A compared plan costs $60 per month but offers unlimited text messaging."

The cost of the plan is simply $60 per month. Since it has unlimited texts, it makes no difference how many texts you use in a month. Al texts are included.

Answer 7

I started with the second plan because it is easier to write an equation for since it is a simpler plan.

Answer 8

Yes but idk how to add $.20 per text if x is already for monthly cost

Answer 9

Ok

Answer 10

Let y = monthly cost.
Let x = number of texts per month.

Second plan:

y = 60

Answer 11

Ok but wouldn't it b y=60x?

Answer 12

Do you understand why the second plan is simply y = 60?
It is because no matter how many texts are used, the price is always $60 per month.

Answer 13

Yea I do understand Tht part

Answer 14

x is the number of texts used in one month.
The second plan has unlimited texts, so the price of each text is $0.
You could write the equation for the second text as

y = 60 + 0x

which means the cost is $60 plus $0 per text. Since $0 per text will end up being $0 no matter how many texts are sent, you simplify

y = 60 + 0x to just

y = 60

Answer 15

Oh! So the equation for the first one would b y=40+.25x??

Answer 16

Now let's look at the first plan.
The first plan also has a fixed monthly amount. It is $40 instead of $60.
Now you do need to pay for each text, and each text costs $0.20.
If you use x number texts, the x number of texts will cost you x * 0.20 which can be written as 0.20x.

That means the firs plan costs:

y = 40 + 0.20x

Answer 17

You're on the right track, but the texts cost $0.20 each, not $0.25 each, using the first plan..

Answer 18

yea Thts wht I meant Idk y I added the 5

Answer 19

After all the discussion, here is the answer:

First plan: y = 40 + 0.2x
Second plan: y = 60

Answer 20

I think you got it now.

Answer 21

Yes thanks do u think u could help me with one more probables like Tht one it's the last one I need to find

Answer 22

Sure. Pls start a new post.

Answer 23

ok