Math Doubts

Perpendicular Lines

perpendicular lines

The intersecting lines which contain right angle between them are called perpendicular lines.


Straight lines are often intersected in a plane in geometrical system. Occasionally, they get intersected by an angle of $90$ degrees (right angle).

In this case, the straight lines are called as perpendicular lines.


$\small \overleftrightarrow{AB}$ and $\small \overleftrightarrow{CD}$ are two straight lines and they are intersected by an angle of $90^\circ$ in a plane at point $\small O$. Therefore, the straight lines $\small \overleftrightarrow{AB}$ and $\small \overleftrightarrow{CD}$ are said to be perpendicular to each other.

example of perpendicular lines
  1. $\small \overleftrightarrow{AB}$ is called as perpendicular line to $\small \overleftrightarrow{CD}$, and represented by $\small \overleftrightarrow{AB} \perp \overleftrightarrow{CD}$.
  2. $\small \overleftrightarrow{CD}$ is called as perpendicular line to $\small \overleftrightarrow{AB}$, and denoted by $\small \overleftrightarrow{CD} \perp \overleftrightarrow{AB}$.

Follow us
Email subscription
Math Doubts
Math Doubts is a best place to learn mathematics and from basics to advanced scientific level for students, teachers and researchers. Know more
Follow us on Social Media
Mobile App for Android users Math Doubts Android App
Math Problems

Learn how to solve easy to difficult mathematics problems of all topics in various methods with step by step process and also maths questions for practising.

Learn more