I have 3 equations in 5 variables: f1(*x, y, z, a, b*)=0, f2(*x, y, z, a, b*)=0, and f3(*x, y, z, a, b*)=0. These equations determine a 3D surface in *x-y-z* coordinate system. How to plot it? For 1 equation in 3 variables: f(*x, y, z*)=0, I can use **ContourPlot3D** to get the surface; For equations expressed in an explicit form: *x=x(a, b)*, *y=y(a, b)*, *z=z(a, b)*, I can use **ParametricPlot3D**. But I failed when I faced this issue introduced above. Please help me. Thanks a lot for your support! The equations are given below. I am trying to obtain the surface in the *S-yh-xd* coordinate system. ``` M = 1; roo = 0.01; yd = 2; 2 M (xh^2 - (yh + 1)^2)/(xh^2 + (yh + 1)^2)^2 + 2 S ((xh - xd)^2 - (yh + yd)^2)/((xh - xd)^2 + (yh + yd)^2)^2 + J/(2 yh) == 0, M*xh (yh + 1)/(xh^2 + (yh + 1)^2)^2 + S (xh - xd) (yh + yd)/((xh - xd)^2 + (yh + yd)^2)^2 == 0, J*Log[2 yh*J/roo] + 2 M (yh + 1)/(xh^2 + (yh + 1)^2) + 2 S (yh + yd)/((xh - xd)^2 + (yh + yd)^2) == Log[2/roo] + 1 ```