Hi, I had problem solving one question. Please help me. I included my answers. Please check to make sure that my way is right. 1. IF f(x,y) = x^2 +4y^2, find the gradient vector f(2,1) and use it to find the tanenet line to the level curve f(x,y) = 8 in the xy-plane at the point (2,1). I solved this way: f(x,y) = x^2 + 4y^2 gradient f(x,y) = <fsubx, fsuby> fsubx = 2x fsuby = 8y therefore, gradient f(x,y) = <2x,8y> gradient f(2,1) = <4,8> f(x,y) = 8 HOW DO I FIND THE EQUATION OF TANGENT LINE????? - I know how to find the equation of tangent plane, but i dont know how to find line. If you can tell me how to find it, i would greatly appreciate your help and intellect. AND, please make sure that What i did until now is right. Thank you so much.