Unit 2 Review Answers
1-2. Study your cards (definitions, postulates, and theorem)
5.
Statements
4(x+5)=24
4x + 20 = 24
4x = 4
x=1
Reasons
Given
Distributive Property
Subtraction Property
Division Property
6.
Statements
8 + 3(x + 2) = 7(x + 6)
8 + 3x + 6 = 7x + 42
3x + 14 = 7x + 42
14 = 4x + 42
-28 = 4x
-7 = x
Reasons
Given
Distributive Property
Combine Like Terms
Subtraction Property
Subtraction Property
Division Property
7.
Statements
2(x + 4) = 4x + 2
2x + 8 = 4x + 2
2x = 4x -6
-2x = -6
X=3
Reasons
Given
Distributive Property
Subtraction Property
Subtraction Property
Division Property
8.
Statements
7x – 2(2x + 3) = 12
7x – 4x -6 = 12
3x - 6 = 12
3x = 18
X=6
Reasons
Given
Distributive Property
Combine Like Terms
Addition Property
Division Property
9.
Statements
1. PQS  SQR
2. mPQS  mSQR
3. mPQS  mSQR  mPQR
4. mPQS  mPQS  mPQR
5. 2 mPQS  mPQR
PQS SQR
1
2
6. mPQS  mPQR
Reasons
Given
Definition of congruent
Angle Addition Postulate
Substitution (2 into 3)
Addition
Division
10.
Statements
M is the midpoint of AB
AM = MB
AM + MB = AB
AM + AM = AB
2AM = AB
AM = 1/2AB
Reasons
Given
Definition of a midpoint
Segment Addition Postulate
Substitution Property
Combine Like Terms
Division Property
11.
Statements
mAOB  mBOC
mAOB  mBOC  180
mAOB  mAOB  180
2mAOB  180
mAOB  90
AOB is a right angle
OA  OB
Reasons
Given
Linear Pair Postulate
Substitution Property
Combine Like Terms
Division Property
Definition of a right angle
Definition of Perpendicular Lines