42. Error Analysis Describe and correct the error made in factoring 9×2 squared – 49=(9x + 7) (9x – 7)

Question

42. Error Analysis Describe and correct the error made
in factoring
9×2 squared – 49=(9x + 7) (9x – 7)

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Thiên Hương 4 years 2021-08-13T04:28:07+00:00 1 Answers 14 views 0

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  1. Sapo1
    0
    2021-08-13T04:29:15+00:00
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    Answer:

    (3x + 7)(3x – 7)

    Step-by-step explanation:

    9x² – 49 ← is a difference of squares and factors in general as

    a² – b² = (a + b)(a – b) , then

    9x² – 49

    = (3x)² – 7²

    This is where the error has been made in that 9x has been used instead of 3x

    = (3x + 7)(3x – 7) ← in factored form

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