Constrain linear objects to be perpendicular to one another. If one line is rotated, the other constrained line adjusts to remain perpendicular to the first line. The lines do not need to be perpendicular when you place the constraint; the first line rotates to become perpendicular to the second line.
To constrain lines to be perpendicular:
Click the Constrain Perpendicular tool from the Dims/Notes tool set.
Multiple dimensional constraint tools share the same position on the tool set. Click and hold the mouse on the visible tool to open the Pop-out Tools list and select the desired tool.
Click the line to constrain.
The cursor switches to the bull’s-eye cursor.
Click the line to be constrained.
A green perpendicular constraint is drawn, connecting the two lines.