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
Among these angles, ∠1 and ∠3, ∠2 and ∠4 are opposite angles.
Video Examples: Vertical or Opposite Angles
Solved Example on Opposite Angles
Ques: 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
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.