Given: Angle A B C and Angle F G H are right angles; Line segment B A is parallel to line segment G F; Line segment B C is-congruent-to line segment G H Prove: Triangle A B C Is-congruent-to Triangle F G H Triangles A B C and F G H are shown. Triangle F G H is slightly lower and to the left of triangle A B C. Lines extend from sides B A and G F to form parallel lines. Another line connects points F and C. Angles A B C and F G H are right angles. Sides B C and G H are congruent. Step 1: We know that Angle A B C Is-congruent-to Angle F G H because all right angles are congruent. Step 2: We know that Angle B A C Is-congruent-to Angle G F H because corresponding angles of parallel lines are congruent. Step 3: We know that Line segment B C is-congruent-to line segment G H because it is given. Step 4: Triangle A B C Is-congruent-to Triangle F G H because of the ASA congruence theorem. AAS congruence theorem. third angle theorem. reflexive property.