Chapter 2.1: Exploring Patterns

Question 1

Line Segment

Answer 1

(or simply segment) AB consists of the endpoints A and B and all points on the line AB that lie between A and B.

Question 2

Ray

Answer 2

the ray AB, or AB consists of the initial point A and all points on AB that lie on the same side of A as B lies.

Question 3

Opposite Rays

Answer 3

on the line AB if C is between A and B, then CA and CB are opposite rays.

Question 4

Collinear

Answer 4

points, segments, or rays that are on the same line are collinear.

Question 5

Angle

Answer 5

an angle consists of two different rays that have the same initial point. The rays are the sides of the angle and the initial point is the vertex of the angle.

Question 6

Acute Angle

Answer 6

an acute angle is an angle with measure greater than 0 and less than 90.

Question 7

Right Angle

Answer 7

a right angle is an angle with a measure of 90.

Question 8

Obtuse Angle

Answer 8

an obtuse angle is an angle with measure greater than 90 and less than 180.

Question 9

Straight Angle

Answer 9

a straight angle is an angle that measures 180.

Question 10

Interior of an Angle

Answer 10

every non straight angle has an interior. A point D is in the interior of /_ A if it is between points that lie on each side of the angle.

Question 11

Exterior of an Angle

Answer 11

every non straight angle has an exterior. A point D is in the exterior of /_ A if it is not on the angle or in the interior of the angle.

Question 12

Adjacent Angles

Answer 12

tow angles are adjacent if they share a common vertex and side, but have no common interior points.