need help with geometry

Discussion in 'General Off-Topic Chat' started by Zenith94, Nov 21, 2008.

  1. Zenith94
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    Zenith94 1337 h4x0r f0r t3h w1nz

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    ok this is really pissing me off now i need to find the y-intersept of a segment without a graph (its that y=mx+b thing) i basically need to find B so say I have a segment that starts at (2,5) and ends (8,9) how to do i find B? i dont know my teachers are retarded
     
  2. Zenith94
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    Zenith94 1337 h4x0r f0r t3h w1nz

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    hurry up
     
  3. MystikEkoez

    MystikEkoez GBAtemp Fan

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    Use the two set of points to find the slope. (m)
    Then plug in one of the set of points and solve for b.
     
  4. Banger

    Banger Me > | | < You ..Wanna Line dance?

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    Yet you are the one that can not figure it out?
     
  5. MystikEkoez

    MystikEkoez GBAtemp Fan

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    Zing!
     
  6. *~Arc

    *~Arc Newbie

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    First you have to find the slope(m). To find the slope you take two points[(2,5) and (8,9)] and make it so (9-5)/(8-2) which is a slope of 2/3.
    Substitute that in for m.[y=2/3x+b]
    Next Substitute one of the two points into the equation. [5=(2/3)(2)+b]
    Solve for b. [5-(4/3)=b]
    Simplify. [11/3=b]
     
  7. MystikEkoez

    MystikEkoez GBAtemp Fan

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    . . . If you tell him how to do it, he won't learn anything.
    Way to fail. I hope someone comes and chops off your nuts so you won't have the ability to reproduce thus improving the future of the universe.
     
  8. DarkLG

    DarkLG Wow One Shiny Ribbon!!!!

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    That's how you learn stuff by showing how to do it,not by figuring it out for yourself cause then you won't know if your right.
     
  9. Dark

    Dark GBAtemp Advanced Fan

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    [​IMG] Lols, that sounded really mean [​IMG] [​IMG]
     
  10. Seven

    Seven oh hell no

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    Well, that's why you do it wrong first, then later when people actually give him the right answer, he'll see why he's wrong and he'll be less likely to make the same mistake twice.

    Not knowing if you're right is moot. If you have an answer, give it, and if you're wrong, well, that's too bad, you can learn from mistakes. No one said he had to be right.
     
  11. junk_man32

    junk_man32 Banned

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    lol, ur asking gbatempers, srsly!
     
  12. nin10do

    nin10do GBAtemp Fan

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    FAIL:


    this is what happens if you don't read the question carefully. the segment STARTS at 2,5 and ENDS at 8,9.

    that means it doesn't pass through the y axis therefor there is no Y intercept.
     
  13. MystikEkoez

    MystikEkoez GBAtemp Fan

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    ROFLMAO. Owned.
     
  14. Zenith94
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    Zenith94 1337 h4x0r f0r t3h w1nz

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    i mean those are 2 points it is a LINE i messed up

    and when i said my teachers are retarded i mean they CANT teach
     
  15. Zenith94
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    Zenith94 1337 h4x0r f0r t3h w1nz

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    thanks dude i just didnt know i could substitue the y for one of the two points in y=2/3x+b

    that clears so much up
     
  16. xcalibur

    xcalibur Gbatemp's Chocolate Bear

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    You'll never learn maths untill you practice and I really suggest that you do another question on your own.
    Arc did the question right and nin10doh is a tard for reading too much into the wording of the question.
    He can't do a simple maths question yet you trust his english skills completely?
     
  17. nin10do

    nin10do GBAtemp Fan

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    hey i was merly pointing out that being able to express yourslef clearly is important. knowing something but not able to put it into proper words can land you a low grade.
     
  18. nin10do

    nin10do GBAtemp Fan

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    i find this way easier:



    y=mx+c ------eq1 put the first coordinates in here
    y=mx+c ------eq2 put the second coordinates in here.

    5=2m+c -------eq1
    9=8m+c -------eq2

    you have two equations and two unkowns. there is a finite set of answers. simultaneously solve them.
    multiply eq1 with 8 and eq2 with -2 to get:

    40=16m+8c -----eq1
    -18=-16m-2c -----eq2

    adding the two equations together gives:

    22=6c
    c=22/6
    simplify
    c=11/3