Question

Determine whether statement (3) follows statements (1) and (2) by the Law of Detachment or Law of Syllogism. If the conclusion is invalid, write invalid and explain why it is invalid.

(1) If two angles are vertical, then they are congruent.
(2) Angle 1 and angle 2 are congruent.
(3) Angle 1 and angle 2 are vertical angles.