This pdf includes the following topics:- Types of Angles Triangle Sum Theorem Exterior Angle Theorem
1. Math Virtual Learning 8th Grade Math Interior/Exterior Angles of a Triangle April 10, 2020
2. 8th Grade Math Lesson: April 10 Learning Target: Student will identify interior and exterior angles of a triangle. Lesson Includes: 1) Angle Types 2)Triangle Sum Theorem 3) Exterior Angle Theorem
3. Warm Up Activity On a piece of paper, identify the following angles.
4. Warm Up Activity Answers Review the questions from the previous slide. Acute Right Obtuse Acute
5. Instruction: Types of Angles Read through the vocabulary and review the diagrams. Then watch the video linked here. 1) Interior Angle: an angle inside a shape 2) Exterior Angle: is an angle outside of a shape, made by the side of a shape and a line drawn out from an adjacent side 3) Acute Angle: an angle that’s less than 90 degrees 4) Obtuse Angle: an angle that is greater than 90 5) Right Angle: a 90 degree angle 6) Complementary Angle: two angles that when added together equal 90 degrees Today we are 7) Supplementary Angle: two angles that when added mainly focusing on Interior and together equal 180 degree Exterior Angles!
6. Practice: Types of Angles On a piece of paper: Identify the exterior and interior angles shown in the problems. 1) 2) 3) 4)
7. Practice: Types of Angles ANSWERS On a piece of paper: Identify the exterior and interior angles shown in the 1) 2) 3) 4)
8. Instruction: Triangle Sum Theorem Read through the theorem and steps. Watch the provided video here. Then review the examples on the next slide. The triangle sum property states that the sum of the three interior (inside the triangle) angles in a triangle is always 180 degrees. 1) Write an equation that adds all three angle 2) Set the equation equal to 180 degrees. 3) Solve for the variable. 4) Plug the value of the variable (the answer) back into any Don’t forget your steps angle expression that you need to find the value of. for solving equations!
9. Instruction: Triangle Sum Theorem Review the examples. Directions: Solve for the variable, then find the missing angle(s).
10. Practice: Triangle Sum Theorem On a piece of paper: Solve for the variable, then find the missing angle(s). Question 1 Question 2 Question 3
11. Practice: Triangle Sum Theorem Answers Check your work from the previous slide. Additional practice linked on the last slide. Question 1 Question 3 Question 2
12. Instruction: Exterior Angle Theorem Read through the theorem and steps. Watch the provided video here. Then review the examples on the next slide. The measure of an exterior angle of a triangle is equal to the sum of the measures of the two remote interior angles. What if you are not given all the angles? 1) Write an equation: remote interior angle + remote interior angle = exterior angle 2) Solve for the variable. 3) Plug the value of the variable (the answer) back into any angle expression that you need to find the value of.
13. Instruction: Exterior Angle Theorem Review the examples.
14. Practice: Exterior Angle Theorem On a piece of paper: Solve for the variable, then find the missing angle(s). 3.
15. Practice: Exterior Angles Theorem Answers Check your work from the previous slide. Additional practice linked on the last slide. Question 1 Question 3 Question 2
16. Additional Practice: Click on the links below to get additional practice and to check your understanding! Types of Angles Triangle Sum Theorem Exterior Angle Theorem * May need to click twice for the links *