What are two lines in the same plane that intersect at right angles?

Hint: Here in this question we have been asked what are two lines in the same plane that intersect at right angles are called for answering this question we will recall the definition of right angle, perpendicular lines, and the angle subtended at the point of intersection.

Complete step-by-step answer:
Now considering from the question we have been asked what are the two lines in the same plane that intersect at right angles are called perpendicular lines.
From the basic concepts we know that the definition of perpendicular lines is given as that the two lines should intersect at the right angles and they should lie in the same plane.
The angle subtended by the perpendicular lines at the point of intersection is a right angle.
The value of a right angle is given as ${{90}^{\circ }}$ .

Therefore we can conclude that the two lines in the same plane that intersect at right angles are called perpendicular lines.

Note: In the process of answering questions of this type we should be sure with the concepts that we are going to apply. This is a purely theoretical based question which can be answered accurately in a short span of time. Similarly parallel lines are known as the two lines lying in the same plane and they should not intersect each other. That means the angle subtended will be ${{0}^{\circ }}$ .