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nixole
nixole asked in Science & MathematicsMathematics · 2 years ago

i need some help on this algebra problem, with the quadratic formula?

“Solve 8x = x^2 - 9 using the Quadratic Formula, Show all work?”

4 Answers

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  • ?
    Lv 7
    2 years ago

    8x = x^2 - 9

    x^2 - 8x - 9 = 0

    25 - (x - 4)^2 = 0

    5^2 - (x - 4)^2 = 0

    -(x - 9)(x + 1) = 0

    x = -1, 9

  • Como
    Lv 7
    2 years ago

    --

    x² - 8x - 9 = 0

    x = [ 8 ± √(64 + 36) ] / 2

    x. = [ 8 ± 10 ] / 2

    x = - 1 , 9

  • mizoo
    Lv 7
    2 years ago

    ax^2 + bx + c = 0

    d = b^2 - 4ac

    x = (-b ± √d)/(2a)

    in your case, a = 1, b = -8, c = -9

    d = (-8)^2 - 4(1)(-9)

    d = 100

    x = (-(-8) ± √100)/(2 * 1)

    x = (8 ± 10)/2

    x = -1, 9

  • llaffer
    Lv 7
    2 years ago

    You can learn what was shown in the previous question and you can solve for this yourself.

    /question/index?qid=20190...

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