Question

when (overline{ad} perp overline{de}) and (overline{ad} perp overline{ab}), (overline{de}) ? (overline{ab})

Explanation:

Step1: Recall the definitions of parallel, perpendicular and skew lines

Parallel lines are coplanar and do not intersect. Perpendicular lines are intersecting and form a right - angle. Skew lines are non - coplanar and do not intersect.

Step2: Analyze the position of \(DE\) and \(AB\)

Since \(AD\perp DE\) and \(AD\perp AB\), \(DE\) and \(AB\) are not parallel (because if two lines are both perpendicular to a third line in the same plane, they would be parallel, but here \(DE\) and \(AB\) are not in the same plane). Also, \(DE\) and \(AB\) do not intersect. So, they are skew lines.

Answer:

neither, they are skew lines