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Pre-Calc-Please check my answer

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Please help-I'm stuck really bad
Thank you for any help you can provide


What are the roots of the equation x^2 -4x + 3 = 0
x^2 - 4x = 3
x^2 +2(-2)x + -2^2 = -3 = -2^2
x^2 + -4x + 4 = 1
(x + -2)^2 = 1
qrt (x+-2)^2 = sqrt 1
x+-2 = plus or minus 1
therefore x=1
x=3 roots are 1 and 3

  • Pre-Calc-Please check my answer -

    You did this about the most difficult way.

    Consider:
    x^2-4x-3=0
    (x-1)(x-3)=0
    x= 1, or 3

  • Pre-Calc-Please check my answer -

    x^2 -4x + 3 = 0
    factor
    (x-3)(x-1) = 0
    x = 3 or x = 1
    or complete the square as you tried
    x^2 -4 x = -3 note sign change of 3
    x^2 - 4 x + 4 = -3 +4 = 1
    (x-2)^2 = 1
    x = 2 +/- 1
    x = 1 or x = 3

  • Pre-Calc-Please check my answer -

    I believe you are trying to factor the polynomial.
    so x^2 -4x+3

    (x-1)(x-3) =0
    x= 1,3

  • Pre-Calc-Please check my answer -

    Alison, I am sure Sheila was trying to do it by completing the square. Note taking half of the coef. of x and squaring it. Factoring is too easy.

  • Pre-Calc-Please check my answer -

    I did do it the long way-you way is much simpler Thank you all

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