## AcidRa1n 3 years ago Determine whether y varies directly with x. If so find the constant variation. y = 12x ****** The answer is Yes; 12 I dont understand how this is the answer. Can someone help me?

1. Nameless

my guess would be that its because y is equal to whatever 12(x) is going to be.

2. Nameless

but that seems too easy

3. AcidRa1n

i know. How about y = 4x+1

4. AcidRa1n

the asnwer is no

5. Nameless

i am probably in over my head.. sorry

6. lgbasallote

here's something you can remember... if y and x are in one line...then it's a direct variation if either y or x is in the denominator...then inverse variation

7. lgbasallote

$y = kx \leftarrow \; \text{direct variation}$ $y = \frac kx \leftarrow \; \text{inverse variation}$

8. AcidRa1n

ok so how does that apply to my first problem

9. lgbasallote

y = 12x <--in the for y = kx <--can you see that?

10. lgbasallote

in the form*

11. AcidRa1n

oh ok so how does it arie directly with x.. Im sorry im just not seeing the picture

12. AcidRa1n

varie* My teacher isnt that good

13. lgbasallote

look at what i said above about y = kx

14. AcidRa1n

yeah I know but what does K mean how the flutter does it varie with anything?

15. lgbasallote

k is a constant

16. lgbasallote

it is called the proportionality constant

17. lgbasallote

it means its value doesnt matter because it is constant..in other words...always stays the same

18. AcidRa1n

ok now I get why 12 is there.. So now explain the rest please?

19. lgbasallote

in your terms... k is the constant variation

20. lgbasallote

first tell me... do you agree that y = 12x is in the form y = kx?

21. AcidRa1n

is y = k? which is 12? and how does that varie to x?

22. AcidRa1n

Yeah I get that

23. lgbasallote

what do you see as difference between $\huge y = kx$ and $\huge y = 12x$

24. AcidRa1n

yeah I see that

25. lgbasallote

spot the difference

26. lgbasallote

not the similarity

27. AcidRa1n

yeah

28. lgbasallote

what do you mean yeah?

29. AcidRa1n

I spot the difference

30. lgbasallote

what's the difference??

31. AcidRa1n

32. lgbasallote

RIGHT! that's why 12 is the constant variation

33. lgbasallote

because k is the constant variation..and k = 12

34. AcidRa1n

ohhh K= Constant Variationnnnnn

35. lgbasallote

yes!

36. AcidRa1n

lmfao face to palm**

37. AcidRa1n

38. lgbasallote

the answer to that one was "NOT direct variation" right?

39. AcidRa1n

yes

40. lgbasallote

that's because of the 1 y = 4x + 1 is not in the form y = kx because of that 1

41. AcidRa1n

what about y - 6x = 0

42. AcidRa1n

;)

43. lgbasallote

simplify it first

44. lgbasallote

solve for y first

45. AcidRa1n

can you do it?

46. AcidRa1n

I dont wnana get confused

47. lgbasallote

48. AcidRa1n

49. lgbasallote

6x..not 6

50. AcidRa1n

yeah

51. AcidRa1n

y-=6x?

52. AcidRa1n

im a idiot

53. lgbasallote

y-?

54. AcidRa1n

lmfao it was negative

55. AcidRa1n

OH NVM

56. AcidRa1n

alright so the answer is 6!

57. lgbasallote

yes

58. AcidRa1n

what about y _ 3 = -3x

59. AcidRa1n

-

60. lgbasallote

what do you think?

61. AcidRa1n

62. AcidRa1n

y= x?

63. lgbasallote

you can't combine 3 and 3x

64. AcidRa1n

is that a constant variation?

65. lgbasallote

66. AcidRa1n

Ah forget about that one can you help me with proportions? i'll open up a new question

67. lgbasallote

i have to go soon

68. AcidRa1n

awe ur like the best lol

69. lgbasallote

call saifoo or amistre

70. AcidRa1n

eh Saifoo is a fool now he used to be cool

71. AcidRa1n

amistre doesnt help me anymore

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