SOLUTION: Your cell phone plan charges you $.02 to send a text message and $.07 to recieve a text message. You plan to spend no more than $5 a month text messaging. a. Write an equation in

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Question 173784: Your cell phone plan charges you $.02 to send a text message and $.07 to recieve a text message. You plan to spend no more than $5 a month text messaging.
a. Write an equation in standard form that models the possible combinations of sent text messages and received text messages.
b. Graph the equation from part (a). Explain what the intercepts of the graph mean in this situation.
c. List three other possible combinations of the number of messages you can send and receive.
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
Your cell phone plan charges you $.02 to send a text message and $.07 to receive a text message. You plan to spend no more than $5 a month text messaging.
:
a. Write an equation in standard form that models the possible combinations of sent text messages and received text messages.
:
Let x = messages received
let y = messages sent
:
.07x + .02y = 5
:
b. Graph the equation from part (a). Explain what the intercepts of the graph mean in this situation.
:
convert equation to the general form
.02y = 5 - .07x
y = - x
y = 250 - 3.5x
:
Plot these two points
x | y
-------
20 |180
60 | 40
Your graph should look like this:

Note: y axis are the no. messages sent, x axis are the no. of messages received
;
The y intercept (250) means only sent messages, none received (x=0)
The x intercept, approx 71 messages received, none sent (y=0)
:
:
c. List three other possible combinations of the number of messages you can send and receive.
you can do this;
You can get the approximate x/y values from the graph or;
To be exact, choose a value for x and find y in the above equation
:
Did this make sense to you. Any questions?