Geometry Vocabulary
What is a point?
A location in space with no size or dimension.
Name a figure that has two endpoints.
A line segment.
If a straight angle measures __ degrees, what is its measure?
180 degrees.
What does the Segment Addition Postulate state?
If B is between A and C, then AB + BC = AC.
Solve for x: 2x + 10 = 50.
x = 20.
What is the definition of a ray?
A part of a line with one endpoint that extends infinitely in one direction.
What do you call a part of a line that extends infinitely in one direction?
A ray.
If segment AB = 7 and segment BC = 5, what is the length of segment AC?
12 units.
What does the Angle Addition Postulate state?
If a ray lies inside an angle, the sum of the two smaller angles equals the larger angle.
If two angles are supplementary and one is 3x while the other is 5x, find x.
x = 22.5.
What does it mean for two segments to be congruent?
They have the same length.
Identify an angle that measures exactly 90 degrees.
A right angle.
Two angles are complementary. One measures 40 degrees. Find the other angle.
50 degrees.
If two angles form a linear pair, what is their sum?
180 degrees.
Find x if segment AB = 4x - 5 and segment BC = 2x + 7, and AB = BC.
x = 6.
Define complementary and supplementary angles.
Complementary angles sum to 90 degrees; supplementary angles sum to 180 degrees.
What is a pair of opposite angles formed by two intersecting lines?
Vertical angles.
If angle ABC = 5x and angle DEF = 2x + 24, and they are congruent, find x.
x=8
What is true about vertical angles?
They are always congruent.
Two angles are vertical. One is 6x - 8, and the other is 4x + 12. Find x.
x = 10.
Explain the difference between collinear and coplanar points.
Collinear points lie on the same line; coplanar points lie on the same plane.
Name the type of angle that measures more than 90 degrees but less than 180 degrees.
An obtuse angle.
A segment is bisected, and one half is represented by 3x + 2, while the other half is 5x - 4. Solve for x.
x=3
If two lines form congruent adjacent angles, then the lines must be this.
What is perpendicular?
Ray BD bisects angle ABC. If angle ABD = 2x+4 and angle DBC = 3x-1, find x.