New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    The roots of the equation 9 (x+9)² = 441

    are:
    A 2,16 Correct Answer Incorrect Answer
    B 12,21 Correct Answer Incorrect Answer
    C –12,–21 Correct Answer Incorrect Answer
    D –2,–16 Correct Answer Incorrect Answer

    Solution

    9 (x+9)² = 441 9(x2+81+18x) =441 x2+81+18x =49 x2+18x+32=0 x2+16x+2x+32 =0 x(x+16) +2(x+16) =0 (x+16) (x+2) =0 When x+16=0 then, x=-16 when x+2 =0 x= -2. (-2, -16)

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