Exploring the Exterior Angle Triangle Sum Theorem

The video tutorial covers the exterior angle theorem and the triangle sum theorem. It begins with an introduction to the learning targets, followed by a 'See Think Wonder' activity to engage students in thinking about angles. The video then provides a detailed explanation of both theorems, including how to apply them to solve problems. Several examples are worked through to demonstrate problem-solving techniques. The session concludes with final questions and a discussion on the application of these theorems.

What are the two main theorems discussed in today's lesson?

• Exterior Angle Theorem and Triangle Sum Theorem

• Pythagorean Theorem and Angle Bisector Theorem

• Pythagorean Theorem and Midsegment Theorem

• Angle Bisector Theorem and Midsegment Theorem

Tags

CCSS.8.G.A.5

What is the learning target for today's lesson?

• To understand the Pythagorean Theorem

• To apply the Exterior Angle Theorem and the Triangle Sum Theorem

• To learn about the Midsegment Theorem

• To solve algebraic equations

Tags

CCSS.8.G.A.5

What does the Exterior Angle Theorem state?

• The exterior angle is equal to the difference of the two remote interior angles

• The exterior angle is equal to the interior angle

• The exterior angle is equal to the sum of the two remote interior angles

• The exterior angle is half the sum of the interior angles

Tags

CCSS.8.G.A.5

What is the sum of the interior angles of any triangle?

• 360 degrees

• 180 degrees

• 90 degrees

• 270 degrees

Tags

CCSS.8.G.A.5

How do you recognize a problem that involves the Triangle Sum Theorem?

• It has a line extended outside the triangle

• It involves a right triangle

• It involves an isosceles triangle

• It has three angles inside the triangle

Tags

CCSS.8.G.A.5

In the problem where you need to determine the value of 3x, what theorem is used?

• Pythagorean Theorem

• Angle Bisector Theorem

• Exterior Angle Theorem

• Triangle Sum Theorem

Tags

CCSS.HSG.CO.C.9

What is the value of x when solving the equation 2x + 54 = 100?

• 46

• 30

• 23

• 54

Tags

CCSS.4.MD.C.7

When solving for x in the equation 10x + 81 = 21x + 4, what is the first step?

• Add 4 to both sides

• Subtract 4 from both sides

• Subtract 10x from both sides

• Add 10x to both sides

What is the smallest angle in a triangle with angles 5x + 20, 9x + 18, and 44 degrees when x = 7?

• 55 degrees

• 30 degrees

• 81 degrees

• 44 degrees

Tags

CCSS.8.G.A.5

Who is correct in the final problem, Nidelli or Grisel?

• Grisel

• Neither

• Nidelli

• Both

Tags

CCSS.1.G.A.1

CCSS.2.G.A.1