Get rid of syms x y for now . Make it a function of x and y by attaching the function handle to it like so f x , y Use meshgrid instead and then the surf function to plot X , Y meshgrid 1010 Z fX , Y surfX , Y , Z Find the max and minimum of the Z vector hereThe saddle point requires us to be a bit creative . You ' re going to use syms x y here to find fx and fy like you ' ve done already but get rid of the 0 . I just want the equations in their symbolic form . Copy those two symbolic equations into another file and make a function out of it . function F whatthefucka F 1 insert fx here F 2 insert fy here endHere ' s the creative part , you ' re going to CtrlF and replace all the x ' s with a 1 and y ' s with a 2 . Save the fileGo back to your original file and write fuckingsolution fsolvewhatthefuck , 2 1 the 2 1 is where I think the saddle point is based on the graph . Hit run on that mother fucker and you got your three variables .