• If \( \Large 2x^{2}+12x+18=0 \), what is the value of x ?

    A) 3

      B) 2

    C) -3

      D) -2

    Correct Answer:
    C) -3

    Description for Correct answer
    Given equation is

    \( \Large 2x^{2}+12x+18=0 \)

    = \( \Large x^{2}+6x+9=0 \) [divide by 2]

    = \( \Large x^{2}+3x+3x+9=0 \) [by factorisation method]

    = \( \Large x \left(x+3\right)+3 \left(x+3\right)=0 \)

    = \( \Large \left(x+3\right) \left(x+3\right)=0 \)

    = \( \Large \left(x+3\right)^{2}=0 \)

    = x+3 = 0

    = x = -3

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