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Math Help - sum of intergers

  1. #1
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    sum of intergers

    The sum of the squares of three consecutive positive integers is 245. What are the integers?
    Last edited by blame_canada100; May 9th 2008 at 02:31 PM.
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  2. #2
    Moo
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    Quote Originally Posted by blame_canada100 View Post
    The sum of three consecutive positive integers is 245. What are integers?
    Hello,

    Isn't there a typo ? Are you sure it's 245 ? Because it has to be a multiple of 3...
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  3. #3
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    x
    X + 1
    x + 2

    3x + 3 = 245


    ps
    I second wat Moo said
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    Hello, blame_canada100!

    The sum of the squares of three consecutive positive integers is 245.
    What are the integers?

    The three integers are: . x,\:x+1,\:x+2

    The sum of their squares is: . x^2 + (x+1)^2 + (x+2)^2 \:=\:245

    . . which simplifies to: . 3x^2 + 6x - 240 \:=\:0 \quad\Rightarrow\quad x^2 + 2x - 80\:=\:0

    . . which factors: . (x - 8)(x+10) \:=\:0

    . . and has the positive root: . x \,=\,8


    Therefore, the integers are: . 8,\:9,\:10

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  5. #5
    o_O
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    Since we're dealing with integers, the solution x = -10 works as well.

    x = -10; x + 1 = -9; x + 2 = - 8

    Their squares should sum of to 245 as well
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  6. #6
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    Ohh thats right! I didnt read the squares part.

    O.O... the OP said they are positive integers.
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