Find the equations for the lines tangent to the graph of xy

Question

Question: 1. Find the slope of the curve x² + 3y² = 7 at (2, -1).

2. Assume y is a differentiable function of x and that y+sin y+x² = 9. Find dy/dx at the point x = 3, y = 0.

3. Find the equations for the lines tangent to the graph of xy + y² = 4 where x = 3.