Conditionals
Biconditionals
Algebraic Proof Reasons
Geometric Proof Reasons
Parallel Lines Proof Reasons
100

The if part of a conditional is the hypothesis. 

The then part of a conditional is the ________.

conclusion

100

A biconditional is only true if the conditional and it's __________ is true. 

converse

100

x+5=14

x=9


What is the reason for this step?

Subtraction Property of Equality

100

∠1 ≅ ∠2 and ∠2 ≅ ∠3

Using transitive property... what conclusion can be drawn?

∠1 ≅ ∠3

100

Given: q||s

Which reason justifies why angle 3 and 6 are congruent?

Alternate Interior Angles

200

A conditional statement is also known as an ______ statement.

if/then

200

Is this biconditional true or false?

If false, state a counterexample. 

A shape is a trapezoid if and only if it has four sides. 

False: rectangle

200

4x+7+8x=19

12x+7=19

What is the reason for this step?

Simplify or combine like terms

200

Fill in the reasons. 

Given: M is the midpoint of AB.

1. AM=MB  1. ______________________

2. 4x+13=3x+17   2.____________________

Definition of midpoint

Substitution

200

What reason justrifies why angle 1 and 2 are congruent?

Corresponding Angles

300

Write the statement as a conditional. 

Angles that form a linear pair are supplementary. 

If two angles form a linear pair, then they are supplementary. 

300

Is the CONVERSE of this statement true or false? If false, give a counterexample. 

If you live in in Missouri, then you live in the United States.

False, Texas

300

33=3(2x+7)  given

33=6x+21  _______________

12=6x Subtraction POE

2=x Division POE

x=2 ___________________

Distributive property and symmetric property

300

What reason matches this step?

QR+RS=QS

Segment Addition

300

Which statement matches this reason?


m∠4+m∠7=180

Same-Side Interior Angles

400

Write the statement as a conditional. 

You live in Missouri if you live in Sedalia. 

If you live in Sedalia, then you live in Missouri.

400

If it is raining, then I use an umbrella.

If I use an umbrella, then it is raining. 

Write this statement as a biconditional. 

It is raining if and only if I am using an umbrella. 

400
Given 3x+2=8


Prove: x=2

3x+2=8  given

3x=6  Subtraction property of equality

x=2   division property of equality

400

Which reason matches this step?

m∠AOB+m∠BOC=m∠AOC

Angle Addition

400

Fill in the reasons.

1. ∠1≅ ∠9 Reason: ________________

2. ∠9≅ ∠16 Reason: _______________

3. ∠1≅ ∠16 Reason: _______________

1. Corresponding 2. Alternate Exterior 3. Transitive Property

500

Determine if the conditional is true or false. If false, give a counter example.

If two angles are supplementary, then one angle is acute and one is obtuse. 

False, two right angles

500

A line bisects a segment if and only if it intersects at its midpoint. 

Write the two statements that form this biconditional. 

Then determine if the biconditional is true or false. 

If a line bisects a segment, then it intersects at the segments midpoint. 

If a line intersects at a segments midpoint, then it bisects the line. 

True 

500

Given: 4(x+2) +6x = 22

Prove: x=2

4(x+2)+6x=22  given

4x+8+6x=22  distributive property

10x+8=22   simplify

10x=14 subtraction property of equality

x=1.4   division property of equality

500

Fill in the reasons for each step. 

1. ∠ABD and ∠DBC are supplementary 

Reason: ___________________

2. m∠ABD+m∠DBC = 180 

Reason: ___________________

1. Linear Pair 

2. Definition of Supplementary

500

Which lines would be parallel if angle 2 and 3 were congruent? What reason?

p||r, Converse of the Alternate Exterior Angles Theorem