Which statement correctly describes perpendicular lines?

Which statement correctly describes perpendicular lines?

• A. Lines that lie in different planes
• B. Lines that are parallel
• C. Lines that intersect to form right angles
• D. Lines that never intersect

Answer: (C)

Perpendicular lines are lines that intersect and form a right angle. When two lines cross and the angle at their intersection measures 90 degrees, they are perpendicular. They must share a plane, since any two intersecting lines lie in the same plane. If lines never meet or are parallel, they cannot be perpendicular. So the defining statement is that they intersect to form right angles.

Perpendicular lines are lines that intersect and form a right angle. When two lines cross and the angle at their intersection measures 90 degrees, they are perpendicular. They must share a plane, since any two intersecting lines lie in the same plane. If lines never meet or are parallel, they cannot be perpendicular. So the defining statement is that they intersect to form right angles.