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## mercedies 2 years ago i need help:

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1. joshi

with...

2. mercedies

$\sqrt{4x-y}=3d$

3. mercedies

solve for x

4. scarydoor

You can square both sides, to start with.

5. mercedies

kk

6. joshi

oh do you just need x by itself? i thought you wanted like actual values. ok phew

7. mercedies

lol

8. scarydoor

getting x by itself is getting the actual values.

9. joshi

no i meant like a numerical value

10. scarydoor

it would be a numerical value. Determined by unknown d and variable y.

11. mercedies

ok

12. mercedies

i have know idea what to do

13. joshi

did you square both sides?

14. mercedies

ya

15. joshi

what did you get

16. mercedies

umm idk

17. joshi

what do you mean? well i got 4x-y=9d^2

18. mercedies

$\sqrt{4x-y}=3d$ummm

19. mercedies

i need to solve for x

20. joshi

well squaring both sides would get you (squareroot 4x-y) ^2 = (3d)^2

21. mercedies

how do you get ^2

22. joshi

and so now you're squaring a square root. it's like (squareroot of 4)^2 square root of 4 is 2 right? so it would be 2^2 which is 4 again. so basically if you're squaring a square root, you're not really doing anything so the square root and square cancel each other out if that makes sense

23. joshi

oh ^2 means sqaure

24. mercedies

oo

25. joshi

so you get how to square both sides then?

26. mercedies

idk this is my first time doing this or a problem like this

27. joshi

oh ok well have you done questions like this: x^2 = 25

28. mercedies

ya

29. mercedies

that would be 5 ya

30. joshi

yeah this question is pretty much the same thing

31. mercedies

oo

32. joshi

so in the x^2=25 you basically square rooted both sides. so square root of x^2 = square root of 25 x=5 but it in this question you have to square both sides, give it another try

33. mercedies

so you square the 3d

34. joshi

yup and also the sqrt 4x-y

35. mercedies

so would it be 9d

36. joshi

9d^2 but yeah

37. mercedies

kk then what do i do

38. joshi

did you also square the other side?

39. mercedies

so would it be 16x-y^2

40. joshi

no because remember its squareroot of 4x-y already. so squaring it gets you squareroot of 4x-y times squareroot of 4x-y which is just 4x-y

41. mercedies

so it stays the same

42. joshi

yeah

43. joshi

can you solve it now? you just have to get x by itself

44. mercedies

would the square roots still be there

45. joshi

no

46. mercedies

k

47. mercedies

so it would look like 4x-y=9d

48. joshi

ok well you should also probably ask your teacher this too cause in math it's really important to know why things happen

49. joshi

yeah exactly

50. mercedies

kk i dont have a teacher

51. joshi

oh...how does that work?

52. mercedies

well my mom is my teacher but my mom is in the hospital

53. joshi

ohh ok

54. mercedies

ya

55. mercedies

how do i get x by it's self

56. joshi

sorry if you dont mind me asking, what grade are you in? like technically, like your age

57. mercedies

14 in 9

58. joshi

so in an equation whatever you do to one side, you have to do to another. so you could add y to both sides which would get you 4x by itself

59. joshi

sorry again, (none of my business i know) but why don't you go to school?

60. mercedies

so what i got was 4x=9dy drama and lot of fighting

61. joshi

that's right except that it's d^2 not just d

62. joshi

oh, well i'm sorry. hope it works out, whatever it is

63. mercedies

oo k

64. mercedies

thank you well we are having hard times my bf just got put in jail for a year

65. joshi

aww :/ Imagine all the people, living life in peace... *swaying to the awesome music* sorry, only thing i could think of

66. joshi

It's good that you're doing math and stuff though

67. mercedies

lol thank you hes only 15

68. joshi

i thought you couldn't go to jail unless you're an adult? well i suppose different countries

69. mercedies

ya well i live in hawaii so there is only two jails and one prison and a whole lot of bad kids they do what they have to

70. joshi

ohh the kids do what they have to?

71. mercedies

ya well know that i look back at what happened it is his own problem

72. joshi

oh. well anyways good luck. time heals

73. mercedies

ya kk so know what do i do with 4x=9d^2y

74. joshi

oh i thought you'd solved it. well think about, this time entire time you've been doing things to both sides. how would you get x by itself this time?

75. mercedies

you divide 4 on both sides

76. mercedies

because what happens on one side you do to the other

77. joshi

yeah! exactly! :D good job

78. mercedies

thank you so it would be 2.25 d^2y

79. joshi

wait what? so i had 4x=9d^2 + y and so x= (9d^2 + y)/4

80. mercedies

ya and that is what i did then i divided 9/4=2.25

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