At what point on the surface z=5+x^2+y^2 is its tangent plane parallel to z=14. When is it parallel to z=5+10x+2y?
You need to know how to do two things, both which will be in your class notes or textbook:
1. Find the normal to a curve at a point (x, y, z).
2. Find the normal to a given plane.
I suggest you review that material and if you need more help, show what you've done and say where exactly you get stuck.