## anonymous one year ago HelloGoodnight -RECIEVE ONE MEDAL FOR HELPING- QUESTION IN POST

1. Nnesha

goodnight. have a nice dreamz

2. anonymous

$1/5(X-15)+1/9(X+9)=X+7$

3. anonymous

@wolf1728 I don't know how to do this . Do you think you can help me solve it.

4. wolf1728

I made a better graphic of the problem:

5. wolf1728

That becomes 1/(5x -75) + 1/(9X +81) = x + 7

6. anonymous

Okay so can you tell me whats the next step

7. wolf1728

We could multiply both sides by (5x -75) and get 1 + (5x -75) / (9x + 81) = (x +7) * (5x -75)

8. anonymous

Thats the answer or is that step 1

9. wolf1728

That's step 1 I'm guessing you have to solve for x right?

10. anonymous

Okay and yep its solving the equation

11. anonymous

What's next . Sorry I'm trying to figure out this step

12. wolf1728

Here's the next step

13. anonymous

Okay Can you tell me if 1/13 is the answer. I think I'm doing it right but I'm not sure

14. wolf1728

I'm working this out as we speak - I don't have the answer yet. I think I've found a quicker way.

15. anonymous

Okay !

16. wolf1728

I am trying to find a way to get rid of the "1" or the (5x-75) but something always gets left over

17. anonymous

Okay let me see too

18. anonymous

I have the answers but I need to know the steps on how to get them so I can understand it

19. anonymous

kaun academy bro that will help u

20. wolf1728

I'd say the next step MIGHT be multiplying 5x^2 -40x -526 by (9x +81) That would produce a cubic equation equaling (5x -75) which would be difficult to solve. Something should be cancelling here.

21. anonymous

Yes, How'd you get five x squared

22. anonymous

That's thepart I'm kind of confused by

23. wolf1728

Look at the second graphic I posted

24. anonymous

Okay

25. anonymous

Yeah I still don't get it

26. wolf1728

That's about as far as I can go I could try using Excel to get the answer (which I'm doing right now) but it won't show you the method

27. anonymous

Okay that's fine take your time.

28. anonymous

@ganeshie8

29. anonymous

@wolf1728 Excel is going to be a link too?

30. wolf1728

No Excel is just a program for doing calculations and if you know how to program it, you can set it up to do trial and error computations.

31. anonymous

ohhhh ok

32. anonymous
33. Nnesha

facepalm **

34. anonymous

aha what happen nnesha

35. Nnesha

so x-5 and x-9 are not at the denominator $\frac{ x-5 }{ 5} +\frac{ x+9 }{ 9}=x+7$ this is your question right ?

36. wolf1728

Aha - that second graphic you posted is different than the other one you posted

37. Nnesha

leftside) find common denominator

38. anonymous

Ah sorry wolf but to nnesha its 15 so x-15/5

39. Nnesha

ohh yea sorry 15*

40. Nnesha

what's the common denominator ?

41. anonymous

45

42. Nnesha

yes right $\frac{ 9(x-15)+5(x+9) }{ 45 }=x+7$ multiply the numerator of 1st fraction by the denominator of 2nd fraction (9(x-15)) multiply the numerator of 2nd fraction with the denominator of 1st fraction (5(x+9) now distribute parentheses by outside number 9(x-15) ="?? 5(x+9)=??? after that combine like terms

43. anonymous

9+5=14x

44. Nnesha

oh no no you can't add 5 and 9 first you should distribute x-15 by 9 distributive property ? a(b+c) = a*b + a*c =ab +ac

45. Nnesha

9(x-15) = 9 times x + 9 times -15 = ?

46. anonymous

Okay question. How come you switched I thought it was suppose to be 5(x-15)+9(x=9)

47. anonymous

How come it was switched?

48. anonymous

sorry *(x+9)

49. Nnesha

ugh i can't use draw tool >.< well it's like cross multiplication when we find common denominator we should multiply the numerator of 1st fraction by the denominator of 2nd fraction |dw:1442104883666:dw|

50. anonymous

loll okay I don't 100% understand that but I am gonna go with the flow

51. anonymous

9x-75+5x+40

52. wolf1728

How about eliminating the denominators and multiply 45 by (x + 7)

53. anonymous

I thought that 45 was the denominators @wolf1728 and how did you get to this other side of the equation

54. Nnesha

ah sorry https://www.mathsisfun.com/numbers/common-denominator.html here read this i've to go i hope other users explain this better than meh XD lol good luck! :=)

55. wolf1728

9* (x-15) + 5*(x+9) = 45 * (x + 7)

56. anonymous

nooooo stay pls help me finish the problem i get it just not that part @Nnesha

57. anonymous

Ohh okaya @wolf1728

58. wolf1728

That help a little HelloGood Morning?

59. Nnesha

ye but we still have to multiply 9(x-15) + 5(x+9) that's what he didn't understand

60. wolf1728

okay - I'll finish it up if you want me to.

61. anonymous

Okay yeah wolf . and yeah thats the part i didnt understand . Go ahead wolf

62. wolf1728

Okay now we have 9* (x-15) + 5*(x+9) = 45x + 315

63. wolf1728

You see that right?

64. anonymous

okay where'd you get 315 from

65. wolf1728

Multiply 45 * (x + 7) you get 45x + 315 (which is 45*7)

66. anonymous

okay got that.

67. wolf1728

Okay so now we do a little multiplying 9* (x-15) + 5*(x+9) = 45x + 315 that equals 9x -135 can you multiply 5*(x +9)?

68. anonymous

5*x=5x and 5*9=45 5x+45

69. anonymous

where'd the 135 come from

70. wolf1728

That's right so we now have 9x -135 + 5x +45 = 45x +315

71. wolf1728

I multiplied 9 *(x -15)

72. anonymous

okay

73. wolf1728

Now we have to collect the terms in this: 9x -135 + 5x +45 = 45x +315

74. anonymous

okay 9x+5x=14x

75. wolf1728

So, we have 14x -135 + 45 = 45x + 315

76. anonymous

yeah so 45x-14x =31x

77. wolf1728

Very good so we now have -135 + 45 = 31x + 315

78. anonymous

yay!

79. wolf1728

There's more to do though

80. anonymous

-135+45=-90

81. anonymous

lol yeah sorry i was celebrating

82. anonymous

-90=31x+315

83. wolf1728

-90 = 31x + 315

84. wolf1728

Very good and now?

85. anonymous

Okay -90+315=225

86. anonymous

225/-31

87. wolf1728

No not quite yet. -90 = 31x + 315 Now let's add -315 to both sides

88. anonymous

oh -90+-315=-405

89. wolf1728

Right so, -405 = 31x

90. wolf1728

and then x equals ?

91. anonymous

okay so x=-405/-31 !

92. wolf1728

Yes and if we calculate that it equals -13.064516129

93. anonymous

yossssss

94. anonymous

You're the greatest

95. wolf1728

96. wolf1728

Shucks, thanks :-)

97. anonymous

loll You're welcome but really Thank you !

98. wolf1728

you are welcome - glad I stuck it out to get you the answer

99. anonymous

Yes me too like I really appreciate it, my professor said this is going to be the hardest test of the class so i must know the steps

100. wolf1728

okay, now at least you know the steps for this problem. Sorry, I started out with the wrong equation.

101. anonymous

@wolf1728 I'm sorry to bother you but I have one more problem and it's not as hard as the first one i promise. Just need to know these steps . And that's not a problem it was my fault i should've screenshotted it from the jump

102. wolf1728

Yes the screen shot was MUCH easier to read :-)

103. anonymous

Agreed!

104. wolf1728

You have another problem huh?

105. anonymous

Yeah one more I promise lmao

106. wolf1728

okay make it easy :-)

107. anonymous

Okay :)

108. anonymous
109. anonymous

Oh hold one sec I wrote it wrong

110. wolf1728

Yes it can't have two equal signs

111. anonymous

Yeah i meant an + haha but lets move this question to a new post i'll tag you

112. wolf1728

Okay