Conjectures and Counterexamples
Conditions May Apply
Show me the Proof
Algebra Edition
Show me the Proof
Segment Edition
Show me the Proof
Angle Edition
100

Determine if the conjecture is true or false. If false, provide a counter example.

All people from Dallas are also from Texas.

True

100

What is a conditional statement?

If - Then statement
100

What definition, property, or postulate is demonstrated?

If BH = MU, then MU = BH

Symmetric Property of Equality

100

What is the definition of a midpoint?

A point that divides a segment into 2 congruent segments. 

100

Which of the following are vertical angles?

angle XYV and angle WYZ or angle XYW and angleVYZ

200

Determine if the conjecture is true or false. If false, provide a counter example.

"All even numbers are evenly divisible by 2"

True

200

For the following statements, what is the Inverse?

p: I eat many cookies

q: I am very happy

If I don't eat many cookies, then I'm not very happy

200

What property, definition, or postulate is being demonstrated?

If HG = FD, then HG + PI = FD + PI 

Addition Property

200

What property, definition, or postulate is being demonstrated?

If G is between B and F, then BG + GF = BF

Segment Addition Postulate

200

What property, definition or postulate is being demonstrated?

Definition of Perpendicular

300

Determine if the conjecture is true or false. If false, provide a counter example.

"All multiples of 2 are also multiples of 4"

False 6 is a multiple of 2 but not a multiple of 4

300

For the following statements what is the contrapositive?

p: Two angles are a linear pair

q: Two angles are supplementary

If two angles are not supplementary, then those two angles are not a linear pair

300

What property, definition, or postulate is being demonstrated?

Division Property

300

What is the reason for statement 7?

Definition of Congruence

300

What property, definition, or postulate is being demonstrated?

Angle Addition Postulate

400

Determine if the conjecture is true or false. If false, provide a counter example.

"All whole numbers are also natural numbers"

False, 0

400

What 2 statements (conditional, inverse, converse, contrapositive) must be true in order for a conditional to be biconditional?

conditional and converse

400

What is the reason for statement 6?

Simplify

400

What is the reason for statement 6?

Transitive Property

400

If you are Given

m angle 1 + m angle 3 = 90^o

by what reason can you state that 

angle 1 and angle3 

are complementary?

 

Definition of Complementary Angles

500

Determine if the conjecture is true or false. If false, provide a counter example.

"All angles must be adjacent in order to be supplementary"

False, an angle that is 73 degrees and 107 degrees are supplementary but they don't necessarily need to be adjacent

500

Would the following statements create a biconditional statement that is true

p: The measures of 2 angles add to 90 degrees

q: 2 angles are complementary

Yes, the measures of 2 angles add to 90 degrees if and only if the 2 angles are complementary

500

What would be your next statement?

2c = 8

500

What is the reason for statement 4?

Substitution Property

500

What would be the reason for number 6?



Transitive Property