Question 1: In the diagram, identify the pair of vertically opposite angles at the intersection of the two lines.

Answer: Angles A and B

Question 2: Calculate the value of the unknown angle if one of the vertically opposite angles measures 65°.

Answer: 65

Question 3: Identify the pair of vertically opposite angles in the following diagram where two lines intersect, and one angle measures 110°.

Answer: Angles X and Y

Question 4: Construct a diagram where two intersecting lines form four angles, and label a pair of vertically opposite angles.

Answer: Student draws and labels two angles as vertically opposite

Question 5: In a diagram where two lines intersect, if one of the angles is 120°, what is the measure of its vertically opposite angle?

Answer: 120

Question 6: Identify the pair of vertically opposite angles when two lines intersect, and the angles are marked as 45° and 135°.

Answer: Angles 45° and 135° are not vertically opposite; the other pair are.

Question 7: Explain why vertically opposite angles are equal, using a diagram in your explanation.

Answer: Because vertically opposite angles are formed by two intersecting lines, and the angles are equal as they are opposite each other across the intersection point, based on the properties of intersecting lines.

Question 8: Using a diagram, find the value of an unknown angle when two lines intersect, with one angle given as 70° and the other as a vertically opposite angle.

Answer: 70

Question 9: A pair of vertically opposite angles are 85° and another angle in the diagram measures 55°. What is the measure of the unknown angle?

Answer: 85

Question 10: Identify and correct the mistake in the following statement: 'Vertical angles are always supplementary.'

Answer: Vertical angles are always equal, not necessarily supplementary.

Question 11: A diagram shows two lines intersecting, forming angles of 90° and 60°. Identify the pair of vertically opposite angles that are equal and state their measure.

Answer: The two 90° angles are vertically opposite and equal.

Question 12: Challenge: Two lines intersect, forming four angles. If three angles are 40°, 70°, and 110°, determine the measure of the fourth angle, assuming the angles form a valid intersection.

Answer: 40