## GoldRush18 2 years ago Sandra uses two mobile cell phones( a digicel and a lime phone), to make her monthly calls. Sandra budget only \$7000 on telephone calls per month and the cost per minute for digicel and lime are \$5.00 and \$7.00 respectively. a. Write down the algebraic equation for Sandra's budget constraint. b. Graph then Sandra's budget constraint. ( the budget constraint intercepts should be shown clearly on the graph) c. How will an increase in the cost per minute for digicel call affect the budget line's y_intercept, x-intercept and the slope?

1. ChmE

a) 7000 = 5x + 7y , where x is digicel and y is lime

2. GoldRush18

i had that for a and i thought mine was wrong, now im understanding :)

3. ChmE

it could be 7000 > 5x + 7y

4. ChmE

because she can't go over but can be under

5. GoldRush18

oh i get it

6. GoldRush18

bcuz the 7000 is her budget

7. GoldRush18

so wat about part b and c

8. ChmE

part b is asking for a budget constraint line and part be also said equation for budget restraint. I would put 7000 = 7x + 5y as the answer for part a because that is the restraint line. Something that she can't go over

9. ChmE

part b is kinda difficult. You should solve for y so the equation is in y = mx + b form then you can graph it. label your axis according to what cell phone. So if we solve for y, the y axis will be the lime phone

10. ChmE

part c I would just pick an increased amount for the cost per minute. graph that as well, and you should easily be able to see the differences from there

11. ChmE

let me know what you got solving for y or x and I'll check you. You should be fine from there

12. GoldRush18

oh im not good at graphs thats why i need the help

13. GoldRush18

ok i got y=1000 and x=1400

14. ChmE

so those are the intercepts, What is the equation?

15. GoldRush18

|dw:1351254063633:dw|

16. GoldRush18

is it that?

17. ChmE

7000 = 5x + 7y 7000 - 5x = 7y 1000 - (5/7)x = y The graph looks correct.

18. ChmE

lets change the cost of digicel to 10 for easy math sake

19. ChmE

7000 = 10x + 7y (0,1000) (700,0)

20. ChmE

|dw:1351258124097:dw|

21. ChmE

So what do you think the answers are for c

22. GoldRush18

i think that as the cost per minute for digicel increase then the budget line will become steeper, is it?

23. ChmE

Because the x and y can easily be switched between the diff cell phones make sure you are stating your assumption of what x and y are along the way. You shouldn't be wrong because it doesn't say what each should be. That is correct. Technically it gets more negative. laymen's term steeper. What about the intercepts?

24. GoldRush18

ok thanks i knw what u mean but im not sure how to explain it in terms of intercepts.

25. ChmE

Look at the lime intercept of the 2 graphs. Do they change? same for the digicel, do they change

26. GoldRush18

ok the y axis which is lime does not change but the x axis which is digicel changes when price increase, im trying to answer

27. ChmE

correct for lime, it stays the same. How does the digicel change

28. GoldRush18

the digicel changes because there was an increase in the cost.

29. ChmE

correct but in what way does it change? That is how you need to answer this question

30. ChmE

increase of decrease

31. ChmE

or**

32. GoldRush18

oh the x intercept decreases

33. ChmE

right. Good job and good luck

34. GoldRush18

omg thank u so much, im understanding so much better now

35. ChmE

36. GoldRush18

do u have an email address, its in a word document

37. ChmE

wow that assignment is awful

38. GoldRush18

i know right, and its like we have to research it because they haven't though us as yet

39. GoldRush18

taught*

40. ChmE

is this due on monday? If this my my assignment I'd be all over google. Even copy and past questions in. Sometimes you get lucky.

41. ChmE

I took econ 3 years ago. I can't remember the other questions sry.

42. GoldRush18

ok

43. GoldRush18

thanks anyway