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adl_thoo Group Title

Since opening night, attendance at Play A has increased steadily, while attendance at Play B first rose and then fell. Equations modeling the daily attendance y at each play are shown below, where x is the number of days since opening night. On what day(s) was the attendance the same at both plays? What was the attendance? Play A: y = 15x + 76 Play B: y = –x^2 + 36x – 4

  • one year ago
  • one year ago

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  1. Luigi0210 Group Title
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    You could set both equations equal to each other or graph and see where they intersect.

    • one year ago
  2. smokeydabear Group Title
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    Yes, all you are trying to do is find where the two graphs intersect, so setting the two equal to each other will give you the answer.

    • one year ago
  3. adl_thoo Group Title
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    is that my quickest way? i have 40 questions. and im only on 13.

    • one year ago
  4. Luigi0210 Group Title
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    Yes, listen to Miss Bear :P

    • one year ago
  5. smokeydabear Group Title
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    Judging from your previous problems, I think your teacher is emphasizing the quadratic formula, so yes you will have to go through it once again =P

    • one year ago
  6. adl_thoo Group Title
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    UGH , it confuses me badly.

    • one year ago
  7. Luigi0210 Group Title
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    I could give the solution if that'll help speed things along for you?

    • one year ago
  8. smokeydabear Group Title
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    It confuses you? What part of it confuses you?

    • one year ago
  9. adl_thoo Group Title
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    everything.

    • one year ago
  10. adl_thoo Group Title
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    The attendance was the same on day 5. The attendance was 151 at both plays on that day. The attendance was the same on day 16. The attendance was 316 at both plays on that day. The attendance was the same on days 5 and 16. The attendance at both plays on those days was 151 and 316 respectively. The attendance was never the same at both plays. these are my answer choices.

    • one year ago
  11. smokeydabear Group Title
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    It is a strategy used to figure out what value x has to be to make the quadratic equation equal to 0. Does that help?

    • one year ago
  12. smokeydabear Group Title
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    Honestly I am trying my hardest not to solve the problem, both for your practice and to fuel my laziness xD Luigi, would you like to solve it?

    • one year ago
  13. Luigi0210 Group Title
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    Do you want a graph to help visual the equations?

    • one year ago
  14. adl_thoo Group Title
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    it doesnt matter. thats fine.

    • one year ago
  15. Luigi0210 Group Title
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    It's kinda big sorry about the size

    • one year ago
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  16. smokeydabear Group Title
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    Now that you see the intersecting points, you have to realize something about this problem. This is a problem that is using months for the x axis. Tell me why there is in reality only one solution to this problem?

    • one year ago
  17. adl_thoo Group Title
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    okat, hmmm...

    • one year ago
  18. smokeydabear Group Title
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    Don't overthink it, this is more of a common sense thing. Also, you could see the reason using the attendance number as well (y axis).

    • one year ago
  19. Luigi0210 Group Title
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    If I solved it right, and I probably didn't but the exact answer would be \[\frac{ -21+/-\sqrt{761} }{ 2}\]

    • one year ago
  20. Luigi0210 Group Title
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    But it would be the positive answer because you can't have negative units

    • one year ago
  21. adl_thoo Group Title
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    would it be C? The attendance was the same on days 5 and 16. The attendance at both plays on those days was 151 and 316 respectively.

    • one year ago
  22. smokeydabear Group Title
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    Look at what Luigi wrote. You can't have a negative number of people, or negative number of months for that matter.

    • one year ago
  23. Luigi0210 Group Title
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    The points of intersection is (3.2931, 125.397)

    • one year ago
  24. adl_thoo Group Title
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    exactly. so answer C would be correct, right?

    • one year ago
  25. smokeydabear Group Title
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    I may just be looking at the graph wrong, but that shouldn't be it. C is telling you that there are two solutions to this problem. What Luigi and I were trying to tell you is that there is only one valid answer here.

    • one year ago
  26. smokeydabear Group Title
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    Are you understanding what I'm saying?

    • one year ago
  27. Luigi0210 Group Title
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    So what the intersection points are say is that there are 125 people on day 3

    • one year ago
  28. Luigi0210 Group Title
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    Are you understanding this or are getting more confused? :l

    • one year ago
  29. adl_thoo Group Title
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    more confused.

    • one year ago
  30. Luigi0210 Group Title
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    I'm sorry ^_^' what specifically is confusing you?

    • one year ago
  31. smokeydabear Group Title
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    Okay think about it like this. If you were to take exactly what the graph told you as the solutions of the problem, you would have a negative number for something that can't be negative.

    • one year ago
  32. adl_thoo Group Title
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    a lot. idk why i think it is C .. idk ): is it B ?

    • one year ago
  33. smokeydabear Group Title
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    C would make sense if you were just trying to find solutions to the raw graphs, but we are looking at a real life scenario.

    • one year ago
  34. adl_thoo Group Title
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    exactly... so, would it change my answer to B ?

    • one year ago
  35. smokeydabear Group Title
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    I feel like it's A, because the point on the graph looks more like (5, 151) than (16, 316)

    • one year ago
  36. Luigi0210 Group Title
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    You're probably thinking of it as a general graph like bear is saying. But think of it this way. When dealing with real life, is it possible to have negative audience and/or negative days?

    • one year ago
  37. adl_thoo Group Title
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    no.. so, a ,, is correct?

    • one year ago
  38. Luigi0210 Group Title
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    And what are the solution choices? I must of missed them ._.

    • one year ago
  39. smokeydabear Group Title
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    It was (5, 151) for A, and (16, 316) for B. C said that both are true, and D said neither are true.

    • one year ago
  40. adl_thoo Group Title
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    yeah, what she said . ^_*

    • one year ago
  41. Luigi0210 Group Title
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    I'd say D.

    • one year ago
  42. Luigi0210 Group Title
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    But yet again she is the smart one here so..

    • one year ago
  43. smokeydabear Group Title
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    But what is bothering me is why they would consider (16, 316) as a possible solution. It's not even the negative solution... it's not anywhere on the graph xD

    • one year ago
  44. smokeydabear Group Title
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    Maybe the graph is wrong...

    • one year ago
  45. adl_thoo Group Title
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    ahhh , im confused. @primeralph , what would your input be on this question ?

    • one year ago
  46. Luigi0210 Group Title
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    Oops, bear is right I used the wrong equation

    • one year ago
  47. Luigi0210 Group Title
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    it is (5, 151)

    • one year ago
  48. adl_thoo Group Title
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    ohh goodness. so my answer is A ?

    • one year ago
  49. Luigi0210 Group Title
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    I'm so sorry for messing this up D:

    • one year ago
  50. smokeydabear Group Title
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    Oh okay, but I just plugged the B coordinates into the original equations, and it worked.

    • one year ago
  51. smokeydabear Group Title
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    Let me try for A next.

    • one year ago
  52. Luigi0210 Group Title
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    I'm so sorry for messing this up D:

    • one year ago
  53. primeralph Group Title
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    Imma just say, equate the two y's. Find an x. Then plug into any one of the equations.

    • one year ago
  54. adl_thoo Group Title
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    its fine.. & okay, ive gotten so confused. idk what to do :(

    • one year ago
  55. primeralph Group Title
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    @adl_thoo cheeel

    • one year ago
  56. smokeydabear Group Title
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    Okay I just confirmed that it is B

    • one year ago
  57. Luigi0210 Group Title
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    And no you were right the answer is A or whatever the points are

    • one year ago
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  58. smokeydabear Group Title
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    The graph threw me off, I just went brute force and plugged everything in, and only (16, 316) worked.

    • one year ago
  59. adl_thoo Group Title
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    so its B ?

    • one year ago
  60. smokeydabear Group Title
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    But aren't they equal at (16, 316)? Luigi, can you plug in the points into the equations to check?

    • one year ago
  61. Luigi0210 Group Title
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    As it turns out both work :/

    • one year ago
  62. Luigi0210 Group Title
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    So adl was right after all

    • one year ago
  63. smokeydabear Group Title
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    Oh look, my calculator was messing with me. Yes both work.

    • one year ago
  64. smokeydabear Group Title
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    My calculator never did like order of operations -.-

    • one year ago
  65. primeralph Group Title
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    |dw:1368580026141:dw|

    • one year ago
  66. primeralph Group Title
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    yo, was I too late?

    • one year ago
  67. Luigi0210 Group Title
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    Naw :P

    • one year ago
  68. adl_thoo Group Title
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    noo . im still figuring this out.

    • one year ago
  69. smokeydabear Group Title
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    We were struggling for a long time and eventually got it, but your input helps reassure us, or me at least ^^

    • one year ago
  70. primeralph Group Title
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    plug in both 5 and 16 separately into eq A. That gives the number of people

    • one year ago
  71. adl_thoo Group Title
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    Sooo , wasit A B or C ?

    • one year ago
  72. Luigi0210 Group Title
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    My stupidity has made this a bit harder than it needed to be

    • one year ago
  73. Luigi0210 Group Title
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    and C

    • one year ago
  74. smokeydabear Group Title
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    It is C, because both work.

    • one year ago
  75. smokeydabear Group Title
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    That was extremely stressful...

    • one year ago
  76. adl_thoo Group Title
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    lol, itss, yay !! :D thanks guys.

    • one year ago
  77. primeralph Group Title
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    I don't know what the options are. It's really not stressful at all

    • one year ago
  78. adl_thoo Group Title
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    veryyyy !

    • one year ago
  79. primeralph Group Title
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    errr.............I knew what to do.............

    • one year ago
  80. adl_thoo Group Title
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    shoot, i didnt.

    • one year ago
  81. Luigi0210 Group Title
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    It was just because I graphed the wrong equations :l

    • one year ago
  82. smokeydabear Group Title
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    It was only confusing because of Luigi's graph! >:0 But it's okay Luigi, I still wuv you <3

    • one year ago
  83. primeralph Group Title
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    so what did you get?

    • one year ago
  84. Luigi0210 Group Title
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    Next time don't listen to me :P

    • one year ago
  85. adl_thoo Group Title
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    its okay guys :) we got it as The attendance was the same on days 5 and 16. The attendance at both plays on those days was 151 and 316 respectively.

    • one year ago
  86. primeralph Group Title
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    yeah

    • one year ago
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