The correct congruence theorem for Step 4 is the AAS Congruence Theorem.
How to prove the given angles
Given: Angle ABC and Angle FGH are right angles; Line segment BA is parallel to line segment GF; Line segment BC is congruent to line segment GH.
Step 1: We know that Angle ABC is congruent to Angle FGH because all right angles are congruent.
Step 2: We know that Angle BAC is congruent to Angle GFH because corresponding angles of parallel lines are congruent.
Step 3: We know that Line segment BC is congruent to line segment GH because it is given.
Step 4: Triangle ABC is congruent to Triangle FGH because of the Angle-Angle-Side (AAS) congruence theorem. This is because we have established the following congruence conditions: Angle BAC ≅ Angle GFH (Angle), Angle ABC ≅ Angle FGH (Angle), and BC ≅ GH (Side).
Therefore, the correct congruence theorem for Step 4 is the AAS Congruence Theorem.