Lesson 1: Exterior Angle Theorem

Question 1

This theorem states that for any triangle, the measure of an exterior angle is equal to the sum of its remote interior angles.

Answer 1

Exterior Angle Theorem

Question 2

These are the angles inside a triangle.

Answer 2

Interior Angles

Question 3

These are the angles adjacent to the interior angles of a triangle.

Answer 3

Exterior Angles

Question 4

This term means “near or beside” in relation to angles.

Answer 4

Adjacent

Question 5

This term means “outside, far, or opposite” in relation to angles.

Answer 5

Remote

Question 6

This theorem states that the sum of the interior angles of a triangle is always 180°.

Answer 6

Triangle Sum Theorem

Question 7

This theorem helps in determining missing angle measures in a triangle.

Answer 7

Triangle Sum Theorem

Question 8

This postulate states that if two angles form a linear pair, then they are supplementary angles.

Answer 8

Linear Pair Postulate

Question 9

The sum of two supplementary angles is always this.

Answer 9

180°

Question 10

The sum of all exterior angles of a triangle is always this.

Answer 10

360°

Question 11

This is the reason why the exterior angles of a triangle always sum to 360°.

Answer 11

Because each exterior angle forms a linear pair with an interior angle, covering a full rotation around the triangle.