## anonymous 5 years ago someone wanna help me? x squared = 12 ...solve using square root property?

1. anonymous

Take square root of both sides.

2. anonymous

3. anonymous

What is the square root over the two or the three?

4. anonymous

idk?

5. anonymous

6. anonymous

idk how to solve this problem? i dont know what the sqauare root of 12 is. all i no is that it is 3 rad 2......what else do i need to do?

7. anonymous

You keep the 12 under the radical and break it down: 2.2.3 all under the square root sign.

8. anonymous

well...so its not 3 square root of 2?

9. anonymous

Right. Actually it is sq rt 4=2

10. anonymous

how is it the square root of 4?

11. anonymous

sq rt of 12 is equal to sq rt of (4.3)

12. anonymous

Not to confuse you, I was just correcting your statement$2\sqrt{3}$

13. anonymous

so is square root of (x-5) ^ 2 = sqaure root of 2 does x =6?

14. anonymous

What?! You lost me.

15. anonymous

ok i feel dumb. ok solve this using the square root property x-5 ^ 2 =2

16. anonymous

i got 6

17. anonymous

Same process: sq rt of both sides.

18. anonymous

ok i did and got x-5 = 1

19. anonymous

sq rt of 2 is not 1

20. anonymous

o...well 2/2 = 1

21. anonymous

That is correct, but not part of this problem.

22. anonymous

ugh ok so what is the square root of 2?

23. anonymous

Sq rt of 2 is sq rt of 2.

24. anonymous

but i have to simplyfy ? whats the answer of the equartion then? just x-5 = sqr 2?

25. anonymous

You can get a number by using calculator, but since you are studying sq rt you can leave it in that form, same way you left sq rt of 3 in previous problem

26. anonymous

do you no how to compelte the square?

27. anonymous

Yes, it's that thingy where you divide by 2, then square it

28. anonymous

ok x ^ 2 - 8x = 3

29. anonymous

slve by completing the squarue

30. anonymous

You take that thing in front of x, divide it by 2, square it, add it to each side.

31. anonymous

??? can u write it out?

32. anonymous

theres nothing infront of x

33. anonymous

Looks like -8 to me.

34. anonymous

oo yeah i got u

35. anonymous

so it would be 16x ^ 2 - 4x = 19?

36. anonymous

You did more than my instructions said, the x^2 -8x remains part of the equation, the thing you calculated is added but they are apples and oranges you just write it in.

37. anonymous

so how would you write it?

38. anonymous

$x ^{2}-8x+16=3+16$

39. anonymous

ok a couple more.... how would you do 1+5i/3-2i

40. anonymous

Have to look up my old notes, been a while.

41. anonymous

ok

42. anonymous

You have to do conjugation: multiply by (3+2i)/(3+2i)

43. anonymous

wait how can u multiply and divide at the same time??

44. anonymous

its 2AM...im sorry im sooo tired but this is due at 8AM

45. anonymous

You have to manipulate your original problem in order to have something to work with. The choice of conjugation is an off-shoot of the bottom term of your problem. In math you can't change things but you can do tricks, for example if you multiply by 1, you have not changed anything. The thing I told you to multiply is equal to 1.

46. anonymous

ok so how do u solve the problem?

47. anonymous

You use the FOIL method multiply top The top looks like this (1+5i)(3+2i) The bottom is (3-2i)(3+2i)

48. anonymous

i got 13 + 17i

49. anonymous

I assume you are working on the top only, recall FOIL method: First, Outside, Inside, Lasts. Be careful to add only like terms, add apples to apples and oranges to oranges.

50. anonymous

that what i did cuz u said the bottom = 1

51. anonymous

Well, the bottom is not equal to 1, the whole term I introduced is equal to 1. You skip to many steps. Take baby steps, produce the terms of FOIL, eg First is1x3=3

52. anonymous

ok .... this is the answer i got..of its wrong just tell me the answer....... 13+17i / 13-12i

53. anonymous

You can't get that, my first term is 3

54. anonymous

3+ 2i +15i +10i^2 which i^2 = -1 over 9-6i -6 - 4i^2

55. anonymous

?

56. anonymous

That's it you got rid of some of the i's but there is still one left in top, must check notes again.

57. anonymous

ok how do you do 6/cube root of 29?

58. anonymous

Not much you can do with that, if you are work with cube roots like you were with square roots.

59. anonymous

o snap i wrote that wrong... i meant 6/cube root of 2a ^ 2 sorry!

60. anonymous

I am looking over my notes for complex numbers, you are doing everything right; seems the point is to at least get it out of the bottom. Break it down as much you can, final answer would have i in it.

61. anonymous

i need that rationalized

62. anonymous

For these, they just want you to move square root out of the the bottom. So the same process as complex number, you multiply by$\sqrt[3]{2a ^{2}}/\sqrt[3]{2a ^{2}}$

63. anonymous

so it would be 6 cube root 2a ^2 over ????

64. anonymous

If you multiply cube root of something by cube root of something you would get something. So the answer is whatever is under radical.

65. anonymous

2a? is the top right?

66. anonymous

2a^2, yes top is right.

67. anonymous

ok last problem!! square root of 2x+11 =5

68. anonymous

You do the opposite of earlier problems: square both sides.

69. anonymous

7?

70. anonymous

You skipped to many steps. Jumping in shower.

71. anonymous

im going to bed night

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