A yearbook printer charges based on the number of pages printed. Here is a table that shows the cost of some recent yearbooks.

Number of pages | 50 | 100 | 150 | 200 |

cost | 1.75 | 2.55 | 3.35 | 4.15 |

Which equation gives the cost, y, in terms of the number of pages, x?

A. y=0.016x+0.95

B. y=0.016x+1.75

C. y=0.016x+48.25

D. y=52.6x+0.95

Guest Nov 17, 2017

edited by
Guest
Nov 17, 2017

edited by Guest Nov 17, 2017

edited by Guest Nov 17, 2017

#2**+2 **

The costs (y) are going up by 0.80 andthe pages (x) is going up by 50

so the gradient is rise /run = change in y/change in x = 0.8/50 = 0.016

so

y= 0.016x + something

Substitute any of the known values into the equation to find what that something (b) (yintercept) is.

Check by subing in a different pair and checking that it works.

You can post your working if you are not sure that your understand.

Melody Nov 17, 2017

#3**+1 **

the only thing I understood about that answer is that D is definitely not the answer

Guest Nov 17, 2017

#7**+2 **

One known value is

y= 2.55 when x=100

I have told you that y= 0.016x + something

y= 0.016x+b

so

Sub in your known values of x and y to find out the value of b

(which is the y intercept or the cost of prinint irrespective of the number of pages.)

2.55 = 0.016*100 +b

Now you can solve this to get the missing b value.

Melody Nov 17, 2017