Show:
Always Sometimes Never
ID the Postulate
ID the Theorem
Vital Vocabulary
Statements and Reasons
100

The intersection of two planes contains at least two points.

Always

100

Two smaller segments add to make one larger segment?

Segment Addition Postulate (2.9)

100

Vertical angles are congruent? (need a number!)

Theorem 2.10

100

What is the vocabulary term for something we take to be true without a proof?

Postulate

100

1. Angle 1 and angle 2 are a linear pair. (Given) 

2. Angle 1 and angle 2 are supplementary. (?)

Theorem 2.3 Supplement Theorem

200

Three points determine a plane.

Sometimes

200

The intersection of two planes is a _____________. Reference the postulate number also.

Line Postulate 2.7

200

Explains the relationship between angles that are a linear pair? (need a number!) AND What is the relationship?

Theorem 2.3 They are supplementary

200

What is the name for the statement right after the word "then"?

Conclusion

200

1. Angle 1 and angle 2 are a linear pair. (Given) 

2. Angle 1 and angle 2 are supplementary. (Supple. Th.) 

3. m<1 + m<2 = 180. ( ??? )

Definition of supplementary angles

300

Points X and Y are in plane P. Any point collinear with points X and Y will also be in plane P.

Always

300
Which postulate says that two smaller angles add to make a larger angle?
Angle Addition Postulate (2.11)
300

Which theorem describes the relationship between complementary angles? (need a number!) What is that relationship?

Theorem 2.4 They add to 90 degrees.

300
What is the word for a mathematical statement that has been proven?
Theorem
300
State the reason that accompanies each statement in the proof below: 1. B is the midpoint of AC. (Given) 2. AB = BC. ( ??? )
Theorem 2.1 Midpoint Theorem or Definition of Midpoint
400

There are at least two lines through points J and K.

Never

400
A plane is made of at least _____ of what type of points? Reference the postulate.
3 noncollinear points Postulate 2.4 or 2.2
400

If two different angles are each supplementary with a third angle, then the two original angles are ____________. Reference the theorem (need a number!).

Congruent Theorem 2.6

400
A formal proof is also called a ...
Two-column proof
400
State the reason that accompanies each statement in the proof below: 1. AB = BC. (Given) 2. AB + BC = AC. ( ??? )
Segment Addition Postulate (2.9)
500

Any two lines will intersect.

Sometimes

500
If two points are in a plane, then what do you know about the line containing those points? Reference a postulate.
The line is also in the plane. Postulate 2.5
500

Perpendicular lines form ____________________ . Reference a theorem.

4 right angles/or congruent adjacent angles Theorem 2.9/or Theorem 2.11

500
To show that a conjecture is false, you must find a ________________ .
Counterexample
500
Complete the proof below with reasons and statements. 1. 8 - x = 12. (Given) 2. 3. 4. 5. x = -4.
2. -8 -8 (Subtraction POE) 3. -x = 4 (Substitution POE) 4. Divide by -1 (Division POE or Multiplication POE) 5. (Substitution POE)