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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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