Back to Use informal arguments to establish facts about angles and similarity of triangles — Problem 5 · Task Set 25

Use Informal Arguments to Establish Facts About Angles and Similarity of Triangles

Work through each section in order. Show your work where indicated, and state which angle relationship you used to find each answer.

Grade 8·23 problems·~40 min·Common Core Math - Grade 8·container·8-g-a-5

Work through problems with immediate feedback

Fluency Practice

Find each missing angle measure. State the relationship you used.

$A triangle with two interior angles 45 and 80 degrees, with one side extended to form an unknown exterior angle at the third vertex.$

In a triangle, two interior angles measure $45\degree$ and $80\degree$ . A side is extended at the third vertex to form an exterior angle there. Find the measure of that exterior angle, in degrees.