One of the key components of geometry is proving theorems. In this lesson, students will test triangle theorems through whole group practice and independently while participating in a “gallery walk” throughout the classroom.

Learning Objectives

(MATH CONTENT.HSG.CO.C.10) Students will prove theorems about triangles. Theorems include: measures of interior angles of a triangle sum to 180 degrees; base angles of isosceles triangles are congruent; the segment joining midpoints of two sides of a triangle is parallel to the third side and half the length; the medians of a triangle meet at a point.

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