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I have got a system of two equations with two variables (x,y) and a parameter p. I have proved that for each value of p there is a unique solution (x*(p),y*(p)) but it is not solvable analytically. f(x,y,p) is another function. I would like to plot the graph of the function g(p):=f(x*(p),y*(p),p). If someone knows a way to do this with some open source program, that would be great.