Chapter 4.2: Angles of a Triangle

Question 1

Interior Angle

Answer 1

the original three angles of the triangle are interior angles.

Question 2

Exterior Angle

Answer 2

the angles that are adjacent to the interior angles are exterior angles of a triangle.

Question 3

Thm. 4.2 - Triangle Sum Thm.

Answer 3

the sum of the measures of the interior angles of a triangle is 180 degrees.

Question 4

Thm. 4.3 - Third Angles Thm.

Answer 4

if two angles of one triangle are congruent to two angles of a second triangle, then the third angles are also congruent.

Question 5

Thm. 4.4

Answer 5

the acute angles of a right triangle are complementary.

Question 6

Thm. 4.5 - Exterior Angles Thm.

Answer 6

the measure of an exterior angle of a triangle is equal to the sum of the measures of the two remote (nonadjacent) interior angles.

Question 7

Thm. 4.6 - Exterior Angles Inequality Thm.

Answer 7

the measure of an exterior angle of a triangle is greater than the measure of either of the two remote (nonadjacent) interior angles.