Module 2 part 2 Properties of Angles

M2L12: Angles Associated with Parallel Lines

Do Problem Set # 1-10 ●Answer each problem thoroughly and in complete sentences

M2L13: Angle Sum of a Triangle

Objectives: ●Students know the angle sum theorem for triangles; the sum of the interior angles of a triangle is always 180 degrees. ●Students present informal arguments to draw conclusions about the angle sum of a triangle.

●In pairs, answer questions a through e

Challenge answers

Challenge answers:

Exploratory Challenge 2 ●Answer questions a through c

Challenge Answers

Lesson Summary ●All triangles have a sum of interior angles equal to 180 degrees ●We can prove that a triangle has a sum of interior angles equal to that of a straight angle using what we know about alternate interior angles and corresponding angles of parallel lines.

M2L13 Problem Set ●Complete problems 1-9 ●Answer thoroughly and in complete sentences.

Problem Set Answers

3.

M2L14: More on the Angles of a Triangle Warm-Up: What properties do rectangles have? What shapes do we get when we draw a diagonal?

Discussion

Exercise Answers

Exercise Answers:

●What do we need to do the solve for angle x?

●Find angle x ●show work on whiteboard

●What do we need to solve for x? o (it’s different than before)

●Find measure of angle x o it’s different than the last three examples

Mind time: Exercises 5-10

Lesson Summary: ●We learned another proof as to why the interior angles of a triangle are equal to 180º with respect to a triangle being exactly half of a rectangle. ●We learned the definitions of exterior angles and remote interior angles. ●The sum of the remote interior angles of a triangle is equal to the measure of the related exterior angle.

M2L14 Problem Set #1-10

Problem Set Answers: 1.