Chapter 4

Question 1

equilateral

Answer 1

3 congruent sides.

Question 2

Isosceles

Answer 2

At least two congruent sides.

Question 3

Scalene

Answer 3

No congruent sides

Question 4

Acute

Answer 4

3 acute angles

Question 5

Equilangular

Answer 5

Acute triangle with 3 congruent angles.

Question 6

Right

Answer 6

Exactly one right angle.

Question 7

Obtuse

Answer 7

Exactly one obtuse angle.

Question 8

Vertex

Answer 8

Point of Intersection of two sides.

Question 9

Opposite Side

Answer 9

Any side opposite an angle.

Question 10

Adjacent Sides

Answer 10

Any two sides that share a common vertex.

Question 11

Legs (Of a Right Triangle)

Answer 11

Sides adjacent to the right angle.

Question 12

Hypotenuse

Answer 12

Side opposite the right angle.

Question 13

Legs (Of a Isosceles Triangle)

Answer 13

Two congruent sides

Question 14

Base

Answer 14

Non-congruent side.

Question 15

Properties of Congruent Triangles

Answer 15

1. ) Reflexive POC applies to triangles
2. ) Symmetric POC applies to triangles.
3. ) Transitive POC applies to triangles.

Question 16

Interior Angle

Answer 16

Angles formed by the sides of a figure, located in the interior of the figure.

Question 17

Exterior Angle

Answer 17

An angle that is adjacent to an interior angle (Must form a linear pair).

Question 18

Auxiliary Line

Answer 18

Line added to a geometric figure.

Question 19

Triangle Sum Theorem

Answer 19

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

Question 20

Third Angles Theorem

Answer 20

If two angles of one triangle are congruent to two angles of a second triangle, then the third is congruent (There is no such thing as the third sides theorem).

Question 21

Theorem 4.4

Answer 21

The acute angles of a right triangle are complementary.

Question 22

Exterior Angle Theorem

Answer 22

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

Question 23

Exterior Angle Inequality Theorem

Answer 23

The measure of an exterior angle of a triangle is greater that the measure of either of the two non adjacent interior angles.

Question 24

Side-Side-Side (SSS) Congruence Postulate

Answer 24

If three sides of one triangles are congruent to 3 sides of a second triangle, then the triangles are congruent.

Question 25

Side-Angle-Side (SAS) Congruence Postulate

Answer 25

If two sides and the included angle of one triangle are congruent to 2 sides and the included angle of a second triangle, the the triangles are congruent.

Question 26

Angle-Side-Angle Congruence Postulate

Answer 26

If two congruent angles and the included side of one triangle are congruent to two angles and the included side of a second triangle, then the triangles are congruent.

Question 27

Angle-Angle-Side Congruence Theorem

Answer 27

If two angles and a non-included side of one triangle are congruent to two angles and the corresponding bin-included side of a second triangle, then the triangles are congruent (Can use the third angles theorem)

Question 28

Base Angles

Answer 28

Two angles that have the base as part of one side.

Question 29

Base Angles Theorem

Answer 29

If two sides of a triangle are congruent, then the angles opposite them are congruent.

Question 30

Base Angles Converse Theorem

Answer 30

If two angles of a triangle are congruent, then the sides opposite them are congruent.

Question 31

Corollary to Base Angles Theorem and Base Angles Converse

Answer 31

A triangle is equilateral if an only if it is equiangular.

Question 32

Hypotenuse-Leg (HL) Congruence Theorem

Answer 32

If the hypotenuse and lef of one right triangle are congruent to the hypotenuse and leg of a second right triangle, the the two triangles are congruent.

Question 33

Corresponding Parts of Congruent Triangles are Congruent (CPCTC)

Answer 33

Once two triangles are proven congruent, by definition, all remaining corresponding sides are angles are congruent.