Question

    The sum of a positive number 'A' and its square is 240.

    Find the value of (A2 - 7A).
    A 150 Correct Answer Incorrect Answer
    B 120 Correct Answer Incorrect Answer
    C 144 Correct Answer Incorrect Answer
    D 225 Correct Answer Incorrect Answer

    Solution

    ATQ; A + A2 = 240 Or, A2 + A - 240 = 0 Or, A2 + 16A - 15A - 240 = 0 Or, (A + 16)(A - 15) = 0 So, A = 15 or A = -16 Since, 'A' is positive. So, required value = 152 - 15 X 7 = 225 - 105 = 120

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