Sketch an ellipse, parabola, or hyperbola by defining start, end, and control points, as well as a rho value.

In the Sketch toolbar:

Sketch toolbar with Conic tool icon highlighted


  1. Click Conic Feature Icon.
  2. Click to indicate a start point.
  3. Click to indicate an end point.
    1. Optionally, immediately after the conic is created, input a numerical value (or type "=#" to input a variable) for the rho value and press enter. This dimensions the conic without having to use the dimension tool.
  4. To input a variable in any dimension field after the geometry is already sketched, the equal sign (=) is not required. Type "#" to input a variable.

  5. Click to indicate a control point.
  6. If a rho value was not input during step 3a above, the rho dimension field automatically opens. Enter a rho value.

    For example, various rho values yield different shapes:

  • Greater than 0.5 yields a hyperbolic shape
  • 0.5 yields a parabolic shape
  • Less than 0.5 yields an elliptical shape
Example showing various Rho values