I would think this is many solutions, the reason is because, there is no specific answer (y) so, x could be anything because it would have to equal to y, which could also be anything! I hope im right! Sorry if im wrong!
5x²+y²=3
by implicit differentiation we shall have:
10x+2yy'=0
the second derivative will be:
10+2y"=0
2y"=-10
y"=-5
I believe the answer is 90