Which of the following statements about perpendicular lines is true?

Perpendicular lines are defined as lines that intersect at a right angle, which measures exactly 90 degrees. This is a fundamental concept in geometry, where perpendicularity is a key element in constructing various geometric shapes and understanding spatial relationships.

The statement regarding perpendicular lines forming right angles highlights their essential characteristic—this is what distinguishes them from other types of lines that may intersect at different angles, such as acute or obtuse angles. Understanding this relationship is crucial in various applications, including engineering, architecture, and other technical fields where precise measurements and angles are required.

The other statements do not accurately represent the nature of perpendicular lines, as they may suggest incorrect associations with vertical orientations or specific angle measurements that do not align with the definition of perpendicular lines.