Exterior Angles and Interior Angles

This video tutorial explains how to find the unknown exterior angle of a triangle using the exterior angle theorem, which states that the exterior angle is equal to the sum of the two opposite interior angles. The video includes three examples demonstrating this theorem. In the first example, the exterior angle is calculated as 120 degrees by adding two given interior angles of 50 and 70 degrees. The second example also results in an exterior angle of 120 degrees, with both interior angles being 60 degrees. The final example shows an exterior angle of 110 degrees, derived from interior angles of 65 and 45 degrees. The video concludes by reinforcing the theorem's application.

What is the main topic discussed in the video?

• Calculating the unknown exterior angle of a triangle

• Learning about parallel lines

• Understanding the properties of circles

• Finding the area of a triangle

According to the theorem, the exterior angle of a triangle is equal to:

• The sum of the two interior opposite angles

• The difference between two interior angles

• The product of the two interior angles

• The sum of all three interior angles

Which theorem is used to find the exterior angle of a triangle?

• Pythagorean Theorem

• Angle Bisector Theorem

• Triangle Sum Theorem

• Exterior Angle Theorem

What is the sum of the interior angles in a triangle?

• 270 degrees

• 180 degrees

• 360 degrees

• 90 degrees

In the first example, what are the given interior angles?

• 65 degrees and 45 degrees

• 50 degrees and 70 degrees

• 30 degrees and 90 degrees

• 60 degrees and 60 degrees

What is the calculated exterior angle in the first example?

• 110 degrees

• 120 degrees

• 140 degrees

• 130 degrees

What is the exterior angle when the interior angles are 70 degrees and 50 degrees?

• 130 degrees

• 140 degrees

• 120 degrees

• 110 degrees

In the second example, what are the given interior angles?

• 65 degrees and 45 degrees

• 50 degrees and 70 degrees

• 30 degrees and 90 degrees

• 60 degrees and 60 degrees

What is the calculated exterior angle in the second example?

• 120 degrees

• 110 degrees

• 140 degrees

• 130 degrees

What is the exterior angle when the interior angles are 60 degrees and 60 degrees?

• 110 degrees

• 120 degrees

• 130 degrees

• 140 degrees