## horsealot203 Group Title Can someone just explain how to write the system of equations, and then how to graph it? Currently, Jodi has a collection of 44 CDs and Veronica has a collection of 22 CDs. Jodi is adding 2 CDs per month to her collection; Veronica plans to add 4 CDs per month. a. Write a system of equations for this situation. Explain your method. b. Graph the system of equations. Describe your graph. c. In how many months will they have the same number of CDs? What will be the number of CDs? Explain how you found the answer. d. At the end of 2 months, who will have more CDs? one year ago one year ago

1. Brittni0605

Let's let J represent Jodi's collection Let's let V represent Veronica's collection

2. horsealot203

What I had was: Let J represent Jodi, V represent Veronica, and x = the number of months. J = 44 + 2x V = 22 + 4x

3. Brittni0605

That is correct.

4. whpalmer4

So far, so good!

5. horsealot203

Ok. So then how do I graph that? My teacher said that we're supposed to use a graphing calculator.

6. Brittni0605

Do you have a graphing calc?

7. whpalmer4

Well, enter the two equations in your calculator and have it graph them. The point where they intersect is the point where they have the same number of CDs. If you drop a vertical line to the x-axis at that point, you can see how many months it took.

8. Brittni0605

If so, input J=44+2x for y1 and V=22+4x for y2

9. horsealot203

Yes I have a graphing calculator. So put in J=44+2x for y1 and V=22+4x for y2?

10. whpalmer4

I'm an old codger, I've never used one of those new-fangled contraptions, so I can't advise you on the details of which buttons to push :-)

11. horsealot203

Ok, thanks though :)

12. Brittni0605

Yes, you are right @horsealot203

13. horsealot203

Ok, so after I put in J=44+2x for y1 and V=22+4x for y2 how would I describe the graph?

14. Brittni0605

Well, one collection is obviously growing faster than the other based off of the slopes of the lines.

15. horsealot203

Ok, it looks like Veronica's collection is growing faster.

16. horsealot203

So for part c for in how many months they will have the same number of cds, that would be where the two line intersect right? So would I use the number on the y axis for the number of months right?

17. Brittni0605

That will be where your lines intersect. But your y axis is representing the number of CD's. The x axis is your months

18. horsealot203

Or would the y axis be the number of cds, and the x axis the number of months?

19. horsealot203

20. Brittni0605

Yw.

21. horsealot203

Oh, and this is a different question, but how do you give medals for responses?

22. Brittni0605

There's a blue box next to ppl's usernames that says 'best response'..just click the box next to the username you want the medal to go to

23. horsealot203

Ok thanks!

24. Brittni0605

Yw.