Question

which pair of angles are vertical angles?
∠ert and ∠mrc
∠kre and ∠ert
∠krc and ∠crh
∠mrc and ∠krm

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 $\angle ERT$ and $\angle MRC$, they are not vertical angles as they are not formed by the intersection of the same two - line pairs.
• For $\angle KRE$ and $\angle ERT$, they are adjacent angles, not vertical angles.
• For $\angle KRC$ and $\angle CRH$, they are adjacent angles, not vertical angles.
• For $\angle MRC$ and $\angle KRM$, they are vertical angles since they are formed by the intersection of lines $MK$ and $CH$ at point $R$ and are opposite each other.

Answer:

$\angle MRC$ and $\angle KRM$