If using the method of completing the square to solve the quadratic equation x2 – 3x + 20 = 0, which number would have to be added to “compl

Question

If using the method of completing the square to solve the quadratic equation x2 – 3x + 20 = 0, which number would have to be added to “complete the square”?​

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Nho 5 years 2021-08-19T23:21:26+00:00 1 Answers 26 views 0

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  1. King
    0
    2021-08-19T23:22:29+00:00
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    Answer:

             ⁹/₄

    Step-by-step explanation:

    The square is:  a²-2ab+b²

    We have

    x^2-3x

    it’s:   x^2-2\cdot x\cdot\frac32

    so we need:   \left(\frac32\right)^2=\frac94

    x^2-2\cdot x\cdot\frac32+\frac94-\frac94+20=0\\\\(x-\frac32)^2-2.25+20=0\\\\(x-\frac32)^2=-17.75

    witch, of course, means no solution

       

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