# Geometry

A geometric figure created without using tools is an
sketch
2 or more lines that are not in the same plane
skew lines
location in space
point
points where a line segment begins and ends
endpoints
straight continuous arrangement of an infinite number of points
line
Two or more line segments of equal measure
congruent line segments
You ___ a geometric figure when you use only a compass and straightedge
construct
points that are all located on the same line
collinear points
A _ _ is a portion of a line that includes two points and all of the collinear points between the two points
line segment
You can _______ by constructing an exact copy of the original line segment
duplicate a line segment
A flat surface is a
plane
portion of a line that begins with a single point and extends infinitely in one direction/
ray
two or more lines located in the same plane
coplanar lines
When you __ a geometric figure, you use tools such as a ruler, straightedge, compass, or protractor
draw
an angle whose measure is equal to 90 degrees
right angle
an angle whose measure is greater than 90 but less than 180
obtuse angle
a ray that divides an angle into two congruent angles
angle bisector
the two rays that form an angle
sides of an angle
the common endpoint of the two rays that form an angle.
vertex of an angle
to divide into 2 equal parts
bisect
a unit of measure for angles
degrees
an angle whose measure is greater than 0 degrees but less than 90 degrees
acute angle
a basic tool used to measure angles
protractor
two or more angles that have equal measures
congruent angles
an angle whose measure is equal to 180
straight angle
a geometric figure formed by 2 rays that share a common endpoint
angle
a statement that can be written in the form “If p, then q”
conditional statement
is the variable p in the conditional statement(after “If” doesn’t conclude “if”)
hypothesis
is the variable q in the conditional statement (after “then” doesn’t include “then”)
conclusion
A statement that is accepted without proof
Postulate
a statement that can be proven
theorem
If a,b, and c are real numbers and a=b, then a+c=b+c
If a,b,and c are real numbers and a=b, then a-c=b-c
subtraction property
(mirror) If a is a real number, then a=a.
reflexive property
If a and b are real numbers and a=b, then a can be substituted for b.
Substitution property
If a,b, and c are real numbers, then a=b and b=c, then a=c.
transitive property