1. The problem statement, all variables and given/known data Find the tangent vector at the point (1, 1, 2) to the curve of intersection of the surfaces z = x2 + y2 and z = x + y. 2. Relevant equations 3. The attempt at a solution I haven't started the problem, because I'm not sure what the first thing to do is. Do I have to parametrize the equations first? Then what?