Unit 2 Vocabulary

Front 1

point

Back 1

names or indicates a location; capital Latin Letters

Front 2

line

Back 2

a straight path (extends forever); lowercase letter (cursive l)

Front 3

plane

Back 3

a flat surface (extends forever); italicized capital letter; or three noncollinear points

Front 4

collinear

Back 4

two or more points that are part of the same line (share a line)

Front 5

coplanar

Back 5

points, lines, and rays that are in the same plane

Front 6

segment

Back 6

a portion of a line that is all the points between two points called endpoints

Front 7

endpoint

Back 7

a point on an end of a segment or ray

Front 8

ray

Back 8

part of a line that starts at a point and extends in a direction forever

Front 9

opposite rays

Back 9

2 rays that have a common endpoint and form a line

Front 10

postulate/axium

Back 10

statement that is accepted as true without proof

Front 11

Unnamed Postulates (5)

Back 11

1. Through any 2 points, there is exactly one line

2. Through any 3 non-collinear points, there is exactly one plane

3. If two points lie in the same plane, then the line containing those points lies in the plane

4. If 2 lines intersect, then they intersect at exactly one point

5. If 2 planes intersect, then they intersect at exactly one line

Hint 11

regarding lines, points, intersection, and planes

Front 12

Ruler Postulate

Back 12

points on a line can be put into a one to one correspondence with the real numbers

Front 13

Segment Addition Postulate

Back 13

If point B is between points A and C, then AB + BC = AC

Front 14

Different Types of Angles (4)

Back 14

1. Acute Angle: an angle whose measure is between 0 and 90 degrees

2. Right Angle: an angle with a measure of 90 degrees

3. Obtuse Angle: an angle whose measure is between 90 and 180 degrees

4. Straight Angle: measure to 180 degrees

Front 15

angle

Back 15

formed by 2 rays joined at their endpoint

Front 16

adjacent angles

Back 16

two angles that share a ray, but no common interior point

Front 17

LInear Pair Theorem

Back 17

the sum of the measure of a linear pair of angles is 180 degrees

Front 18

Complementary Angles

Back 18

a pair of angles whose measures add to be 90 degrees

Front 19

Supplementary Angles

Back 19

a pair of angles whose measure add to 180 degrees

Front 20

Vertical Angles

Back 20

If 2 lines intersect, then pairs of non-adjacent angles are vertical angles

Front 21

Inductive Reasoning

Back 21

the process of reasoning that a rule or statement is true because specific cases are true

Front 22

Conjecture

Back 22

a statement you believe to be true based on inductive reasoning

Front 23

Counterexample

Back 23

one example that shows the conjecture is not true

Front 24

Conditional Statement

Back 24

a statement of the form if p, then q; where p is the hypothesis and q is the conclusion

Front 25

Other Conditional Statement Forms

Back 25

1. Converse: if q, then p

2. Inverse: if not p, then not q

3. Contrapositive: if not q, then not p

Front 26

logically equivolent statements

Back 26

related conditional statements that have the same truth value: conditional and its contrapositive; converse and inverse

Front 27

deductive reasoning

Back 27

using definitions, postulates, previously proven theorems, and logic to draw conclusions

Front 28

Law of Detachment

Back 28

If p then q is a true statement, then when p is true, q is also true

Front 29

Law of Syllogism

Back 29

If p then q and q then r are true statents and p is true, then p then r is true

Front 30

biconditional statement

Back 30

p if and only q, bothp then p then q and its converse are true

Front 31

reflexive property of equality

Back 31

a = a

Front 32

symmetric prop of =

Back 32

if a = b, then b = a

Front 33

transitive prop of equality

Back 33

if a = b and b = c, then a = c

Front 34

substitution prop of equality

Back 34

if a = b, then b may be substituted in place of a

Front 35

linear pairs theorem

Back 35

if 2 angles form a linear pair, then they are supplementary

Front 36

congruent supplements theorem

Back 36

if 2 angles are supplementary to the same angle (or supplementary to 2 angles), then the 2 angles are congruent

Front 37

vertical angles theorem

Back 37

if 2 angles are vertical angles, then they are congruent

Front 38

right angle congruence theorem

Back 38

all right angles are congruent

Front 39

congruent complements theorem

Back 39

if 2 angles are complementary to the same angle (or 2 congruent angles), then the 2 angles are congruent

Front 40

common segments theorem

Back 40

can pertain to common angles theorem

Front 41

unnamed theorem

Back 41

if 2 congruent angles are supplementary, then they are right angles

Hint 41

relates to right angles

Front 42

parallel lines

Back 42

2 coplanar lines that don't intersect

Front 43

skew lines

Back 43

2 noncoplanar lines that don't intersect

Front 44

perpendicular lines

Back 44

2 lines that intersect on a 90 degree angle

Front 45

transversal

Back 45

a line that intersects 2 coplanar lines at 2 different points; 8 angles are formed

Front 46

corresponding angles

Back 46

angles that are in the same position of the intersection

Front 47

alternate interior angles

Back 47

angle pairs that are in the interior and on alternate sides of the transversal

Front 48

same side interior angles

Back 48

angle pairs that are in the interior and on the same side of the transversal

Front 49

alternate exterior angles

Back 49

angle pairs that are in the exterior and on alternate sides of the transversal

Front 50

corresponding angles postulate

Back 50

if 2 parallel lines are cut by a transversal, then corresponding angle pairs are congruent; converse is true

Front 51

alternate interior angles theorem

Back 51

if 2 parallel lines are cut by a transversal, then the alt. int angles are congruent; it's converse is true

Front 52

alternate exterior angles theorem

Back 52

if 2 parallel lines are cut by a transversal, then the alternate exterior angles are congruent; converse is true

Front 53

same side interior angles theorem

Back 53

if 2 parallel lines are cut by a transversal, then the same side interior angles are supplementary; converse is true

Front 54

parallel postulate

Back 54

through a point P, not on the line l, there is exactly one line parallel to l

Front 55

Unnanmed Theorem

Back 55

if 2 intersecting lines on the same plane form a linear pair of congruent angles, then the lines are parallel

Hint 55

relates to intersecting lines

Front 56

Unnamed Theorem

Back 56

if 2 congruent supplementary, then they are right angles

Hint 56

pertains to right angles