# Plot3d of explanation of partial partial derivatives

I want to plot a two functions together that looks like this:

But I am only able to come up with this;"which is clearly wrong"

Plot3D[{x^2 + x + y^2, x + y}, {x, -20000, 20000}, {y, -20000, 20000}]


I have looked through the help section but somehow I am not getting how to change it.

Ps: I do not care about the range that its plotted in.

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The vertical plane in your figure is not a depiction of a function, as it is multi-valued. Therefore it can't be plotted by Plot3D, which is meant for functions only. – Sjoerd C. de Vries Nov 9 '13 at 8:12

Just a variant plotting all within ContourPlot and using MeshFunctions to highlight variable kept constant.

ContourPlot3D[{x^2 + x + y^2 - z == 0, x == 0}, {x, -2, 2}, {y, -2,
2}, {z, 0, 6}, MeshFunctions -> {#1 &}, Mesh -> {{0.}},
MeshStyle -> {Green, Thick}]


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One way, I am sure there is a better way, but for now....

Remove["Global*"];
eq1 = x^2 + x + y^2;
eqX = x == 0;(*for the yz plan surface*)
lim = 20;
zlim = 800;(*adjust as needed when changing p1*)
p1 = Plot3D[eq1, {x, -lim, lim}, {y, -lim, lim}];
p2 = ContourPlot3D[Evaluate@eqX, {x, -lim, lim}, {y, -lim, lim}, {z, 0, zlim},
ImageSize -> 250];
Show[{p1, p2}, AxesLabel -> {"x", "y", "z"}]


eqY = y == 0; (*for the xz plan  surface *)
`