green edge
increase test scores

Common Core Standards

Angles, Parallel Lines, & Triangles

Grade: 8th Grade

Math.8.G.5 or 8.G.A.5


Use informal arguments to establish facts about the angle sum and exterior angle of triangles, about the angles created when parallel lines are cut by a transversal, and the angle-angle criterion for similarity of triangles. For example, arrange three copies of the same triangle so that the sum of the three angles appears to form a line, and give an argument in terms of transversals why this is so.

8th Grade Math - Angles, Parallel Lines, & Triangles Lesson
green bar
green bar green bar