Name_____________________________________________Date___________________________Period____________
We will be able to: __________________________________________________________________________________
Warm-Up:
a) Given that m∠GFE = 145, use what you know about
linear pairs to find m∠DFE. Show work your work below:
b) Given that m∠GDE = 58 , find m∠DEF using what you know about the sum of the interior angles of a triangle.
c) m∠DEF + m∠GDE = __________
d) m∠GFE = __________
e) Using key vocabulary, describe what you notice about your answers to part c and d.
Triangle Sum
Theorem
Exterior Angle
Theorem
Example 1: Find m∠2. Then, classify the triangle by its angles.
Example 2: Find the value of x and the measure of the exterior angle. Then, classify the triangle by its angles.
