To Apply the Equal Radius Constraint to Circles or Ellipses
1. Click > 
Equal. The Select dialog box opens.
Equal. The Select dialog box opens.2. Select an elliptic or circular entity.
 | If you select an elliptic entity, select Major Axis or Minor Axis from the Ellipse dialog box to define the radius to be constrained. |
3. Select another elliptic or circular entity, and define the radius to be constrained. The constraint is applied.
4. Middle-click or click Cancel. The Select dialog box closes.