Question

which angles are vertical to each other? ∠9 and ∠11 ∠11 and ∠3 ∠4 and ∠11 ∠3 and ∠9

Explanation:

Step1: Recall vertical - angle definition

Vertical angles are formed when two lines intersect. They are opposite each other and are congruent.

Step2: Analyze each option

• For $\angle9$ and $\angle11$, they are vertical angles as they are formed by the intersection of two lines and are opposite to each other.
• $\angle11$ and $\angle3$ are not vertical angles.
• $\angle4$ and $\angle11$ are not vertical angles.
• $\angle3$ and $\angle9$ are not vertical angles.

Answer:

$\angle9$ and $\angle11$