Question

Emma wants to compare some cell phone plans by graphing their cost per text message. Mobilama charges a flat rate of $30 for unlimited texts. Celly-On-The-Go has no set-up charge, but it does charge $0.10 per text. Ringit Wireless only charges $0.05 per text, but it has an account charge of $15.

Explain to Emma how she can graph these cell phone plans and describe what key features of the graphs she should consider when making a decision??

Answer 1

@ganeshie8 @thomaster @iPwnBunnies

Answer 2

"Mobilama charges a flat rate of $30 for unlimited texts." Should be a flat (horizontal) line, because the output is not affected by input.

"Celly-On-The-Go has no set-up charge, but it does charge $0.10 per text." Should have a slope because it is affected by input and the y-intercept should be 0 because there is no account charge limitation.

"Ringit Wireless only charges $0.05 per text, but it has an account charge of $15." Should be same as second line with low slope because it is "0.05" instead of "0.10" but this time with y-intercept because there is account recharge limitation.

Answer 3

so Mobilama is a horizontal line, celly on the go has no y-intercept but has a slope of.10, and ringit wireless has a y intercept and a lower slope than celly?

Answer 4

can you help me with a couple more?

Answer 5

sure, just post, if I can help, I certainly will :)

Answer 6

thanks

Answer 7

and does mobilama have a horizontal line on 30 on the y axis? or is the 30 just there to be there

Answer 8

@imer

Answer 9

???? @imer does that mean mobilamas horizontal line is on 30 on thhe y axis?????

Answer 10

its y-axis, y=30

Answer 11

ok just making sure, and it celly on the go has no y intercept?

Answer 12

Yes, it does not have intercept.

Answer 13

and has a y intercept of 15?

Answer 14

would look something like y=0.10x+0 which is just y=0.1x

Answer 15

and the third one would be y=0.05x+15

Answer 16

sweet thank you so much!