## CCSS.Math.Content.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.

Authors: National Governors Association Center for Best Practices, Council of Chief State School OfficersTitle: CCSS.Math.Content.8.G.A.5 Use Informal Arguments To Establish Facts About... Geometry - 8th Grade Mathematics Common Core State Standards

Publisher: National Governors Association Center for Best Practices, Council of Chief State School Officers, Washington D.C.

Copyright Date: 2010

(Page last edited 10/08/2017)

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