x^2y+xy^2=6. Find d^2y/dx^2 at (1,3). And if it equals A) -18 B) -6 C)6 D) 12 E)18?

2) x^3+y^3=27. find d^2y/dx^2

Please help me with this calculus problem. I am so lost in my class. step by step work would be greatly appreciated. The work does not have to be completely accurate, I just need the steps. Thank you in advance.