25 pairs of vertical angles are formed.
Step-by-step explanation:
Suppose there are N distinct lines, which produces N squared pairs of vertical angles.
If we have 2 distinct lines, then we have 4 pairs of vertical angles are formed.
2 distinct lines, then 2² = 4 pairs of vertical angles
3 distinct lines, then 3² = 9 pairs of vertical angles
4 distinct lines, then 4² = 16 pairs of vertical angles
Here we have 5 distinct lines, and these lines produces 5² pairs of vertical angles.
So here 25 pairs of vertical angles are formed by 5 distinct lines.
