).Use the Perpendicular Snap tool to snap to the perpendicular point of another entity. You can snap to an arc, circle, ellipse, line, polyline, infinite line, ray, spline, or edge of a plane to form a perpendicular alignment with that entity or with an imaginary extension of that entity.
Do one of the following:
).
To form a perpendicular angle (A) to an entity (B), select anywhere on the entity.