Points, Lines, and Planes
All about Segments
All about Angles
Even More About Angles
Vocabulary
100

This has no size, names a location, and is represented by a dot.

What is a point?

100

Point D is located at 50 on the number line.  Point E is located at -20.  This is the length of DE.

What is 70?

100

This figure is formed by two rays with a common endpoint.

What is an angle?

100

This term refers to angles between 0 and 90 degrees.

What is acute?

100

This term describes segments or angles that are the same.

What is congruent?

200

This term describes points that lie in the same plane.

What is coplaner?

200

B is the midpoint of AC.  The length of AB is 4.  This is the length of AC.

What is 8?

200

This term refers to angles between 90 and 180 degrees.

What is obtuse?

200

These two angles sum up to 180 degrees.  They are known as this.

What is supplementary?

200

This term refers to the common endpoint of the two parts making up an angle.  It is also one way to refer to an angle

What is a vertex?

300

This extends forever in only one direction.

What is a ray?

300

This is the point that bisects a segment

What is a midpoint?

300

This ray divides an angle into two angles that are congruent.

What is an angle bisector?

300

Angles A and B are complementary.  Angle A has this measure when angle B is 22 degrees.

What is 68 degrees?

300

These are two nonadjacent angles formed by two intersecting lines.

What are vertical angles?

400

When two lines intersect, they form one of these.

What is a point?

400

B is the midpoint of line segment AC.  AB = 4x — 6, BC = 7x — 18.  This is the length of BC.

What is 10?

400

Refer to the diagram. Angle AOC has a measure of 5x + 3.  Angle DOC has a measure of 2x — 5.  Angle EOD has a measure of 42 degrees.  This is the value of x.

What is 20?

400

Angle B has a measure of 2x — 4.  This is the measure of angle B’s supplement.

What is 184 — 2x?

400

This is a statement that is accepted to be true without proof

What is a postulate?

500

When two planes intersect, they form one of these

What is a line?

500

Refer to the diagram.  This is the length of RT.

What is 70?

500

This is the measure of the interior angle formed by the hands of a clock when it is 4:00

What is 120 degrees?

500

Angle A’s measure is 12 degrees more that half the measure of its linear pair.  This is the measure of angle A.

What is 68 degrees?

500

Point B is between points A and C.  This refers to the fact that AB + BC = AC

What is the segment addition postulate?