Study problems for calculus exam! [admin note: unanswered]

I have a big exam coming up in a few days, and there were a few problems on the study guide I couldn't get. I was hoping you guys might be able to help me out!

The first question I couldn't get goes as follows:

Find an equation of the plane tangent to the surface

3(x^2) - 4(y^2) + 6z = 26

at the point (-2, 1, 3)

Any help on this problem would be GREATLY appreciated! And please don't just give me the answer, it would be much more beneficial if you actually described what was happening. Thank you!