Plot 3D plane given equations in matlab

Question

I want to plot 2 3D planes for the equations given below :

x + y + z = 1
2x - y = 0

For 1st equation, I plotted it using meshgrid as :

[x y] = meshgrid(-5:0.5:5);  
z = 1 - x - y  
mesh(x,y,z)

But for 2nd equation, z is not given i.e. z can be anything, then how do I plot plane for this ?

Answer 1

The comments are correct. It is more of a math problem. You draw a line 2x - y = 0 and translate it for any z value to create a plane.

[x, y] = meshgrid(-5:0.5:5);  
Zv = @(x,y) 1 - x - y;
mesh(x,y,Zv(x,y));

hold on

[x, z] = meshgrid(-5:0.5:5);
Yv = @(x) 2*x;
mesh(x,Yv(x),z);

hold off