This Problem Set is a part of the Lesson 12, Unit 1, Grade 8. In this lesson, students find rigid transformations that show two figures are congruent and make arguments for why two figures Apply the definition of congruence in terms of transformations for polygons on a grid, to decide whether or not two figures are congruent. Apply the definition of congruence in terms of transformations for polygons on a grid, to decide whether or not two figures are congruent. Let's decide if two figures are congruent.