**Definition of Common External Tangent**

- A tangent that is common to two circles and does not intersect the segment joining the centers of the circles is called Common External Tangent.

**More about Common External Tangent**

- A common tangent can either be a common external tangent or a common internal tangent.

**Examples of Common External Tangent**

- In the above figure, line PQ is the common external tangent.

- In the above figure, line AB is the common external tangent.

**Solved Example on Common External Tangent**

Identify the common external tangent from the given figure.

Choices:

A. AB

B. CD

C. EF

D. none of the above

Correct Answer: B

Step 1:A tangent that is common to two circles and does not intersect the segment joining the centers of the circles is called common external tangent.

Step 2:In the given figure, the line CD touches both the circles on the same side of the line is the external tangent to the circle.

Step 3:So, CD is the common external tangent line.

**Related Terms for Common External Tangent**

- Circles
- Common Internal Tangent
- Segments
- Tangents