** Definition of Opposite Angles**

- When two lines intersect, four angles are formed. The angles that are directly opposite to each other are called Opposite Angles.

**More about Opposite Angles**

- Opposite angles are also called vertically opposite angles.
- Opposite angles are always non-adjacent.
- When two parallel lines are cut by a transversal, 8 angles or 4 pairs of opposite angles are formed.

**Example of Opposite Angles**

- In the given figure, the lines
*l*and*p*intersect each other and form four angles. Among these angles, ∠1 and ∠3, ∠2 and ∠4 are opposite angles.

**Solved Example on Opposite Angles**

Find the pairs of opposite angles in the given figure.

Choices:

A. (a, b), (c, d), (e, f), (g, h)

B. (a, e), (b, f), (c, g), (d, h)

C. (a, c), (b, d), (e, g), (f, h)

D. (a, d), (b, c), (e, h), (f, g)

Correct Answer: C

Solution:

Step 1:When two lines intersect, four angles are formed. The angles that are directly opposite to each other are called opposite angles.

Step 2:From the figure, two lines PQ and RS are cut by the transversal TU forming eight angles.

Step 3:So, (a, c), (b, d), (e, g), (f, h) are opposite angles.

**Related Terms for Opposite Angles**

- Adjacent Angles
- Intersect
- Line
- Transversal