Level set in Matlab

Hello everyone

I need to find the function f within x^2+y^2<=100 and the tangential plane at point (4,2,f(4,2)), for 2<=x<=6, 0<=y<=4.

the commend sounds like this:

figure(2); mesh(x,y,z);

axis([-10 10 -10 10 -10 10]); hold on;

[xt,yt]=meshgrid(2:0.2:6,0:0.2:4);

zt=6-1.4*(xt-4)-0.2*(yt-2);

surf(xt,yt,zt,ones(size(xt))*200);

view(42.5,42); xlabel('x'); ylabel('y'); zlabel('z');

what I don't understand is where "zt=6-1.4*(xt-4)-0.2*(yt-2)" comes from...would be thankful for any hint

Edit: thank you for mentioning. done.

[Jan]

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