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    If 9X²+16Y²+ 24 is a perfect square, X and Y being integers, then the smallest possible non-negative value of X + Y is
    Question

    If 9X²+16Y²+ 24 is a perfect square, X and Y being integers, then the smallest possible non-negative value of X + Y is

    A.

    0

    B.

    1

    C.

    2

    D.

    3

    Correct option is C

    Given:

    We need integers
    and  such that:

    9X² + 16Y² + 24 is a perfect square.

    We want the smallest non-negative value of X + Y.

    Solution: (smallest integer):

    Try X = 0:
    Expression = 16Y² + 24 → not a perfect square for any small Y ≥ 0.
    (Checked: 24, 40, 88, 168, 280… none are perfect squares)

    Try X = 1:
    Expression = 9(1)² + 16Y² + 24
    = 33 + 16Y²

    Test small Y:

    Y = 0 → 33 (not square)

    Y = 1 → 33 + 16 = 49 = 7² → perfect square ✔

    So (X, Y) = (1, 1) works.

    Check if anything smaller exists:

    (0,0), (1,0), (0,1)… all failed.
    Thus this is the smallest pair.

    Therefore:

    X + Y = 1 + 1 = 2

    Final Answer: 2

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