Exercise 22 Page 623

We are told that the distances between consecutive bases are the same. Also, the distance between home plate and second base is the same as the distance between first base and third base.

△ STH

Note that HS is shared by both △ HFS and △ STH. Thus, by the Reflexive Property of Congruence, this side is congruent to itself between the triangles. Since we have three pairs of congruent corresponding sides, by the Side-Side-Side Congruence Theorem, △ HFS ≅ △ STH.

△ FST

Note that HS ≅ FT. Since we have three pairs of congruent corresponding sides, by the Side-Side-Side Congruence Theorem, △ HFS ≅ △ FST. Thus, by the Transitive Property of Conguence, the three triangles are congruent to each other.