Question

Refer to the diagram below.

QS is perpendicular to OS. QS is a _____ line.

Answer 1

QS is a _tangential_ line, because QS is perpendicular to OS.

Answer 2

ANSWER

QS is a tangential line.

Step-by-step explanation

From the diagram, OS is a radius of the circle.

The radius can only be perpendicular to QS, if and only if QS touches the circle at, S.

The point S is called the point of tangency.

Since line QS is perpendicular to the radius, OS and QS touches the circle at only one point, it is called a tangent.

Therefore QS is a tangential line.