Determine whether there exists an integer x such that x^2 + 10 is a perfect square.
The Attempt at a Solution:[/B]
Assume x^2 + 10 = k^2 (a perfect square).
Solve for x in terms of k:
x = ±sqrt(k^2 - 10)
Since k is an integer and k^2 - 10 > 0, k > sqrt(10) > 3.
From here (and multiple other approaches), I'm not sure how to continue. Any help in proving whether such an integer value of x exists would be appreciated.