Consider the numbers 2 · 10600 + 15 and 2 · 10600 + 16. Without even attempting to calculate those numbers (they have 601 decimal digits, and even won’t crunch that), prove non-constructively that they cannot both be perfect squares.

step-by-step explanation:

no, her answer is not correct.   we square the lengths of all sides and then determine whether the pythagorean theorem holds here:

9² + 15² = 306.   this is not equal to the square of the longest side ( that square being 395.   answer c is correct.

the awnser is visionary