Question

    Between what values of x is the expression 19x -

    2x2 - 35 positive?
    A 2.5 > x > 7 Correct Answer Incorrect Answer
    B 2.5 < x < 7 Correct Answer Incorrect Answer
    C 2.5 ≤ x ≤ 7 Correct Answer Incorrect Answer
    D 2.5 ≥ x ≥ 7 Correct Answer Incorrect Answer

    Solution

    So, 19x - 2x2 - 35 > 0 Or, 2x2 - 19x + 35 < 0 Or, 2x2 - 14x - 5x + 35 < 0 Or, 2x(x - 7) - 5(x - 7) < 0 Or, (2x - 5) (x - 7) < 0 So, x = 2.5 or x = 7 For any value of 'x' > 7, the value of expression 2x2 - 19x + 35 becomes, positive. So, 'x' lies between 2.5 and 7.

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