2 Prove that a reflection is an isometry, i.e., VP, Q (II): P'Q' = PQ, where P' = MP and Q' = MIQ are the corresponding images under the reflection with respect to the (mirror) line (1). Consider the following two cases: a) P and Q are on the same side of (1). b) P and Q are on opposite sides of (1). c) There are two more cases to be considered. Name them but do not study them. 2 Prove that a reflection is an isometry, i.e., VP, Q (II): P'Q' = PQ, where P' = MP and Q' = MIQ are the corresponding images under the reflection with respect to the (mirror) line (1). Consider the following two cases: a) P and Q are on the same side of (1). b) P and Q are on opposite sides of (1). c) There are two more cases to be considered. Name them but do not study them