Question

mark the and 12

Explanation:

Step1: Recall the definition of vertical angles

Vertical angles are pairs of opposite angles formed by two intersecting lines. They are equal in measure.

Step2: Check each pair

• For \(\angle1\) and \(\angle3\): They are vertical angles (formed by two intersecting lines).
• For \(\angle2\) and \(\angle14\): Not vertical angles.
• For \(\angle1\) and \(\angle6\): Not vertical angles.
• For \(\angle3\) and \(\angle7\): Not vertical angles.
• For \(\angle8\) and \(\angle9\): Not vertical angles.
• For \(\angle5\) and \(\angle12\): Not vertical angles.

Answer:

\(\angle1\) and \(\angle3\)