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Homework Help: Equation : find values

  1. May 4, 2008 #1
    2x^2 − 12x + p = q(x − r)^2 + 10 for all values of x find p q and r

    i've got

    2(x-3)^2 + p = Q(x-r)^2 + 10

    so q = 2 r = 3 and p = 10?

    now the answers say that Q = 2 r = 3 and p = 28?

    can someone explain how to properly go about doing this equation.
     
  2. jcsd
  3. May 4, 2008 #2
    2x^2 − 12x is not the same as 2(x-3)^2
     
  4. May 5, 2008 #3

    HallsofIvy

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    Science Advisor

    If a polynomial equation is true for all values of x, then "corresponding coefficients"- that is, coefficients multiplying the same powers of x on opposite sides of the equation- must be the same: multiply the square on the right and compare "corresponding coefficients".
     
  5. May 5, 2008 #4


    k ive done it now, thx
     
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