Question

Company A rents copiers for a monthly charge of $200 plus 10 cents per copy. Company B rents copiers for a monthly charge of $400 plus 5 cents per copy. What is the number of copies above which Company A's charges are the higher of the two?

Answer 1

200 + 10X=400+5x

Answer 2

that will be the threshold

Answer 3

Then what ?

Answer 4

What did you get for x?

Answer 5

I've gotten that far

Answer 6

x is the number of copies at which the cost of both companies are equal. Anything above that and company A's costs will be higher than B's.

Answer 7

So it's the intersection point on a graph kinda ?

Answer 8

Exactly!

Answer 9

Could I graph this on my ti 83?

Answer 10

Yes, you can graph it on a TI-83...it should be pretty easy. Put in both equations and find the intersection point.

Answer 11

How would it go in y=mx+b form

Answer 12

I tried and got error message

Answer 13

Thanks for help either way

Answer 14

Did you put it in like this?

Answer 15

I had a typo in my earlier earlier equations...but it's fixed in the image.

Answer 16

No little a

Answer 17

Alpha right ?

Answer 18

Doesn't graph :l

Answer 19

The little a you can ignore...it's just a bi-product of the screenshot.

Answer 20

The 3rd and subsequent equations should be blank.

Answer 21

Says window range error

Answer 22

My guess is that your window parameters are set up in some weird way. Click the Windows button on the top row and look them over.

Or, you can just install Microsoft Math (free) which is a pretty cool tool to replace the TI stuff when you're not in class :)

http://www.microsoft.com/en-us/download/details.aspx?id=15702

Answer 23

You can also just use wolfram:

http://www.wolframalpha.com/input/?i=solve+for+x%3A+200%2B.10x%3D400%2B.05x

Answer 24

Yea I bought the app in android just easier sometimes when it's explained lol

Answer 25

I have used some of the android apps too...they work pretty well and I like touch/pinch zooming a lot

Answer 26

I put my x min at - 10 and +10 and like wise for y , and then it graphed

Answer 27

Had to zoom fit to see lines though the look almost parallel

Answer 28

Since you know where it should intersect (at x = 4000 and y = 600) use something like xMin=3999, xMax=4001, yMin=599, and yMax=601...will make it look "decent".

Answer 29

Well let's say I didn't know where it intersects how would I know where to look in equation to alter my window settings

Answer 30

You can use SEC->Calc and choose intersect...I think the TI-83 has that. I'm using a TI- 84

Answer 31

err 2nd->Calc I mean

Answer 32

I did but it gave me error until I changed window settings

Answer 33

That's why I dislike TI's...it's 2012 and they are still not user-friendly.

Answer 34

They should be 1000x faster, touch screen and in color by now. Sadly, all the schools and standard tests use them....so TI has no real reason to make those improvements. <end rant>

Answer 35

Yea I was pulling out my hair until I found this site lol thank you so much , maybe I can get an A on my next online test

Answer 36

No problem...good luck :)