Question

A telephone company charges a fixed monthly rate plus a rate per minute of usage. The company charges $135 for 100 minutes of usage and $375 for 500 minutes of usage. An equation can be written to show the relationship between the total minutes used (x) and the total monthly charges (y). Which of the following best describes the steps to draw the graph of y against x?

Answer 1

Draw a graph which joins the points (135, 100) and (375, 500) and has a slope = 0.6

Draw a graph which joins the points (100, 135) and (500, 375) and has a slope = 0.6

Draw a graph which joins the points (100, 135) and (500, 375) and has a slope = 1.67

Draw a graph which joins the points (135, 100) and (375, 500) and has a slope = 1.67

Answer 2

@campbell_st , @Nnesha

Answer 3

@jim_thompson5910

Answer 4

First off, what are the two points?

Answer 5

Idk

Answer 6

Points: (# of minutes, cost).
You have 2 pairs of minutes and costs. Try to write the points with them

Answer 7

Exactly. So for example, if it says "50 minutes cost $35" then that would translate into the ordered pair (50, 35).

Answer 8

oh okay @jim_thompson5910

Answer 9

so based on that example and what peachpi said, what are the two ordered pairs in this case?

Answer 10

the two ordered pairs are (135,100) and (375,500)

Answer 11

unfortunately you mixed up the cost and minutes

Answer 12

"The company charges $135 for 100 minutes"

means

x = 100
y = 135

x is the minutes
y is the cost

Answer 13

so "The company charges $135 for 100 minutes" is the ordered pair (100,135)

Answer 14

oh okay

Answer 15

what is the other point?

Answer 16

(500,375)

Answer 17

good

Answer 18

so we have

(100,135) and (500,375)

Answer 19

use the slope formula

\[\Large m = \frac{y_{2}-y_{1}}{x_{2}-x_{1}}\]

to find the slope of the line through the two points (100,135) and (500,375)