It is expected that students will specify conditions under which triangles may be similar or congruent and use these relationships to solve problems.
Many applications of geometry involve similarity or congruence of triangles.
Triangles are found in nature, architecture, construction, surveying, computer graphics, and other fields. Developing an understanding of triangle congruency can strengthen reasoning and problem-solving skills. Ask students to measure similar triangles or different sizes and discuss what is the same and what is different. Discuss as a class what conditions must exist for similarity to occur. Display a right triangle on the overhead.