The cost of printing the school newspaper is $60 for 200 copies and $105 for 400 copies. Write a linear equation modeling this data and find the amount of money it would cost to print 485 copies.

Question

texaschic101 · Answer

200/60 = 3.33
400/105 = 3.80
I am not sure....because if you pay 60 for 200 copies, you are paying 3.33 per copy and if you are paying 105 for 400 copies you are paying 3.80 per copy.
I am sorry, I don't know.

anonymous · Answer

Given two points (60, 200) and (105 , 400) you can make a line. The model of the equation will be Ax + By + C= 0 or you can do y = mx +b

anonymous · Answer

thanks this helps

texaschic101 · Answer

does he need to find the slope ?

anonymous · Answer

yes.. it is y2-y1/ x2 - x1.... so its (400-200)/(105-60)..

texaschic101 · Answer

If the slope can reduce, do you reduce it ?

anonymous · Answer

my answer choices are 		
$124.13
$135
$139.13
$165

texaschic101 · Answer

@jim_thompson5910 ...can you help

jim_thompson5910 · Answer

did you guys manage to find the equation?

anonymous · Answer

Here is what I think the solution is .... m = 4.444.... then plug  any of the two points so you choose 400= (4.444)(105) + b so b = -66.66667...

To check I will do the other point as well. 200 = (4.444)(60) + b... b= -66.6667

So now all I do is 485 =(4.4444...)(x) -66.666667...

solve for x. X = 124.13.

So the answer is $124.13.
 I think....

anonymous · Answer

im going to try that

jim_thompson5910 · Answer

mebs you have the coordinates backwards, which gives you the wrong equation, but you did manage to get the correct answer for the second part

anonymous · Answer

o swell... excellent my luck always saves me...

texaschic101 · Answer

m = 200/45 = 40/9

y = mx + b ...using points (105,400)
400 = 40/9(105) + b
400 = 4200/9 + b
400 - 4200/9 + b
3600/9 - 4200/9 = b
- 600 = b

y = 40/9x - 600

I guess I am really way off on this one

jim_thompson5910 · Answer

you also have the coordinates backwards I'm afraid

jim_thompson5910 · Answer

it should be m = 9/40

texaschic101 · Answer

lol......I am so not good at this

jim_thompson5910 · Answer

that's ok, just keep practicing and you'll get better

texaschic101 · Answer

thanks jim....I will

jim_thompson5910 · Answer

yw

anonymous · Answer

so you want the co-ordinates to be (200,60) and (400,105)? What are the correct co-ordinates please explain? @jim_thompson5910

jim_thompson5910 · Answer

the coordinates are in the form (x,y)

where

x = # of copies
y = total cost (to make x copies)

jim_thompson5910 · Answer

so you have it right

anonymous · Answer

o goody thanks

jim_thompson5910 · Answer

yw