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OVERVIEW
Algebra I Content Review Notes are designed by the High School Mathematics Steering Committee as a
resource for students and parents. Each nine weeks’ Standards of Learning (SOLs) have been identified and a
detailed explanation of the specific SOL is provided. Specific notes have also been included in this document
to assist students in understanding the concepts. Sample problems allow the students to see step-by-step models
for solving various types of problems. A “ ” section has also been developed to provide students with
the opportunity to solve similar problems and check their answers. The answers to the “ ” problems are
found at the end of the document.
The document is a compilation of information found in the Virginia Department of Education (VDOE)
Curriculum Framework, Enhanced Scope and Sequence, and Released Test items. In addition to VDOE
information, Prentice Hall textbook series and resources have been used. Finally, information from various
websites is included. The websites are listed with the information as it appears in the document.
Supplemental online information can be accessed by scanning QR codes throughout the document. These will
take students to video tutorials and online resources. In addition, a self-assessment is available at the end of the
document to allow students to check their readiness for the nine-weeks test.
The Algebra I Blueprint Summary Table is listed below as a snapshot of the reporting categories, the number of
questions per reporting category, and the corresponding SOLs.
It is the Mathematics Instructors’ desire that students and parents will use this document as a tool toward the
students’ success on the end-of-year assessment.
4
Expressions and Order of Operations A.1 The student will
a) represent verbal quantitative situations algebraically; and b) evaluate algebraic expressions for given replacement values of the
variables. Expression is a word used to designate any symbolic mathematical phrase that may contain numbers and/or variables. An expression can be represented algebraically… Example 1: 6x + 5 Example 2: a – 9b or in written form. Example 1: The sum of a number and eleven Example 2: One half of a number squared minus four Some common words are used to indicate each operation. Many of these are shown in the table below, but there are others.
Add Subtract Multiply Divide Equals
Plus
Sum
More than
Increased by
Total
All together
Add to
And
Difference
Minus
Less than
Decreased by
Take away
How many left
Remaining
Subtracted by
Less
Times
Product
Multiplied By
Doubled (x2)
Tripled (x3)
By
Squared (a·a)
Cubed (a·a·a)
Part
Quotient
Divided by
Each
Half ( ÷ 2)
Split (÷ 2)
Is
Are
Is Equal To
Is equivalent to
Equals
Expressions and Order of Operations Translate the written expressions to algebraic expressions, and algebraic expressions to written
expressions.
1. the difference of eleven and x
2. three times the sum of a number and ten
3. four times the difference of n squared and five
4. 12g ÷ 4
5. a² - b⁴
5
Expressions are simplified using the order of operations and the properties for operations with real numbers. The order of operations is as follows: First: Complete all operations within grouping symbols. If there are grouping symbols within other grouping symbols, do the innermost operation first. Grouping symbols
include parentheses (a), brackets [a], radical symbols √𝒂, absolute value bars |𝒂|,
and the fraction bar 𝒂
𝒃.
Second: Evaluate all exponents. Third: Multiply and/or divide from left to right. Fourth: Add and/or subtract from left of right. To evaluate an algebraic expression substitute in the replacement values of the variables and then evaluate using the order of operations.
Example 1: 15 − 9 ÷ (−3)2
Step 1: 15 − 9 ÷ (−3)2 Step 2: 15 − 9 ÷ 9 Step 3: 15 − 1
Step 4: The answer is 14
Example 2: (𝑝 − 3)2 + 2𝑝 − 4, 𝑝 = −7
Step 1: (−7 − 3)2 + 2(−7) − 4
Step 2: (−10)2 + 2(−7) − 4 Step 3: 100 + 2(−7) − 4 Step 4: 100 + (−14) − 4 Step 5: 86 − 4 Step 6: The answer is 82
Scan this QR code to go to an order of operations video tutorial!
6
Example 3: 20 − √3 ∙ 10 − 14 + |7 − 5 ∙ 4|
Step 1: 20 − √30 − 14 + |7 − 20|
Step 2: 20 − √16 + |−13| Step 3: 20 − 4 + 13 Step 4: The answer is 29
Expressions and Order of Operations Evaluate each expression. a=2, b=5, x= - 4, and n=10.
6. [𝑎 + 8(𝑏 − 2)]2 ÷ 4
7. (2𝑥)2 + 𝑎𝑛 − 5𝑏
8. 𝑛2 + 3(𝑎 + 4)
9. 𝑏𝑥 − 𝑎𝑥 Evaluate each expression using the order of operations.
10. 63 − √10 ÷ 2 + 2 ∙ 22
11. √75 + (9 + 3)2 − 33
+ 19
12. (7∙3−18)3
√63−14+21
13. |6 − √33 + 22| − 8
Scan this QR code to go to a video for more complicated order
of operations help.
7
Properties of Real Numbers A.4EKS The student will solve multistep linear and quadratic equations in two variables,
including justifying steps used in simplifying expressions and solving equations.
Property Definition Examples
Multiplicative Property
of Zero
Any number multiplied by zero
always equals zero.
𝑎 (0) = 0
0 ∙ (−14) = 0
Additive Identity Any number plus zero is equal
to the original number.
𝑎 + 0 = 𝑎
126 + 0 = 126
Multiplicative Identity Any number times one is the
original number.
𝑎 ∙ 1 = 𝑎
1 ∙ 78 = 78
Additive Inverse A number plus its opposite
always equals zero.
𝑎 + (−𝑎) = 0
−21 + 21 = 0
Multiplicative Inverse
A number times its inverse
(reciprocal) is always equal to
one.
𝑎 ∙ 1
𝑎= 1
5
2 ∙
2
5= 1
Associative Property
When adding or multiplying
numbers, the way that they are
grouped does not affect the
outcome.
(𝑎 + 𝑏) + 𝑐 = 𝑎 + (𝑏 + 𝑐)
5 + (3 + 8) = (5 + 3) + 8
(𝑎𝑏)𝑐 = 𝑎(𝑏𝑐)
6(3𝑎) = (6 ∙ 3) 𝑎
Commutative Property
The order that you add or
multiply numbers does not
change the outcome.
𝑎 + 𝑏 = 𝑏 + 𝑎
14 + 6 = 6 + 14
𝑎𝑏 = 𝑏𝑎
8 ∙ 3 = 3 ∙ 8
Distributive Property
For any numbers a, b, and c:
a(b + c) = ab + ac
5 ( 3 − 2) = 5 ∙ 3 − 5 ∙ 2
−3 (𝑎 + 𝑏) = −3𝑎 + (−3𝑏)
𝑜𝑟 − 3 (𝑎 + 𝑏) = −3𝑎 − 3𝑏
Substitution property of
equality
If a = b, then b can replace a.
A quantity may be substituted
for its equal in any expression.
𝐼𝑓 5 + 2 = 7, 𝑡ℎ𝑒𝑛 (5 + 2) ∙ 4 = 7 ∙ 4
𝐼𝑓 𝑎 = 5, 𝑡ℎ𝑒𝑛 11𝑎 = 11 ∙ 5
8
Reflexive Property of
Equality Any quantity is equal to itself.
𝑎 = 𝑎
5
3=
5
3
Transitive Property of
Equality
If one quantity equals a second
quantity and the second
quantity equals a third, then the
first equals the third.
𝐼𝑓 𝑎 = 𝑏, 𝑎𝑛𝑑 𝑏 = 𝑐, 𝑡ℎ𝑒𝑛 𝑎 = 𝑐.
𝐼𝑓 2 + 4 = 6, 𝑎𝑛𝑑 2(3) = 6,
𝑡ℎ𝑒𝑛 2 + 4 = 2(3)
Symmetric Property of
Equality
If one quantity equals a second
quantity, then the second
quantity equals the first.
𝐼𝑓 𝑎 = 𝑏, 𝑡ℎ𝑒𝑛 𝑏 = 𝑎
𝐼𝑓 25 = 13𝑎 − 1, 𝑡ℎ𝑒𝑛 13𝑎 − 1 = 25
Properties of Real Numbers Match the example on the left to the appropriate property on the right.
1. (𝑥 + 3) + 𝑦 = 𝑥 + (3 + 𝑦)
2. 1 = 1
2𝑥∙ 2𝑥
3. 3𝑥 + 6 = 6 + 3𝑥
4. (5 – 𝑥)2 = 10 – 2𝑥
5. 𝑏5 + 0 = 𝑏5
6. (𝑥 + 3) + 𝑦 = 𝑦 + (𝑥 + 3)
7. 0 ∙ 17𝑛 = 0
8. 5𝑥 + (−5𝑥) = 0
9. 𝑥𝑦𝑧 = 𝑥𝑦𝑧
10. If one dollar is the same as four quarters,
and four quarters is the same as ten dimes,
then ten dimes is the same as one dollar.
A. Multiplicative Property of Zero
B. Additive Identity
C. Multiplicative Identity
D. Additive Inverse
E. Multiplicative Inverse
F. Associative Property
G. Commutative Property
H. Distributive Property
I. Substitution Property of Equality
J. Reflexive Property of Equality
K. Transitive Property of Equality
L. Symmetric Property of Equality
9
Solving Equations
A.4 The student will solve a) multistep linear equations in one variable algebraically;
e) practical problems involving equations and systems of equations.
You will solve an equation to find all of the possible values for the variable. In order to solve an equation, you will need to isolate the variable by performing inverse operations (or ‘undoing’ what is done to the variable). Any operation that you perform on one side of the equal sign MUST be performed on the other side as well. Drawing an arrow down from the equal sign may help remind you to do this.
Example 1: 𝑚 − 9 = −3
+9 + 9
𝑚 = 6
Check your work by plugging your answer back in to the original problem.
6 − 9 = −3
Example 2: 𝑥+4
5 = −12
∙ 5 ∙ 5
𝑥 + 4 = −60
−4 − 4
𝑥 = −64
Check your work by plugging your answer back in to the original problem.
−64 +4
5 =
−60
5= −12
Scan this QR code to go to a video tutorial on two-step
equations.
10
You may have to distribute a constant and combine like terms before solving an equation.
Example 3: −4(𝑔 − 7) + 2𝑔 = −10
−4𝑔 + 28 + 2𝑔 = −10
−2𝑔 + 28 = −10
−28 − 28
−2𝑔 = −38
÷ (−2) ÷ (−2)
𝑔 = 19
Check your work by plugging your answer back in to the original problem.
−4 (19 − 7) + 2(19) = −10
−4(12) + 2(19) = −10
−48 + 38 = −10
If there are variables on both sides of the equation, you will need to move them all to the same side in the same way that you move numbers.
Example 4: 3𝑝 − 5 = 7(𝑝 − 3)
3𝑝 − 5 = 7𝑝 − 21
−3𝑝 − 3𝑝
−5 = 4𝑝 − 21
+21 + 21
16 = 4𝑝
÷ 4 ÷ 4
𝑝 = 4
Check your work by plugging your answer back in to the original problem.
3(4) − 5 = 7(4) − 21 12 − 5 = 28 − 21
7 = 7
Scan this QR code to go to a video tutorial on multi-step
equations.
11
Example 5: 𝑥+10
5𝑥=
−1
5 You can begin this problem by cross multiplying!
5(𝑥 + 10) = −1(5𝑥)
5𝑥 + 50 = −5𝑥
+5𝑥 + 5𝑥
10𝑥 + 50 = 0
−50 − 50
10𝑥 = −50
÷ 10 ÷ 10
𝑥 = −5
Check your work by plugging your answer back in to the original problem.
−5+10
5(−5)=
−1
5
5
−25 =
−1
5
− 1
5 = −
1
5
Solving Equations
Solve each equation 1. 𝑘 + 11 = −8
2. 9 − 3𝑥 = 54
3. −17 = 𝑦−6
2
4. 5 (2𝑛 + 6) + 8 = 33
5. 3 − (4𝑘 + 2) = −15
6. 5𝑔 + 4 = −9𝑔 − 10
7. −2(−4𝑚 − 1) + 3𝑚 = 4𝑚 − 8 + 𝑚
8. 𝑥−4
2=
−2(3𝑥−3)
6
Scan this QR code to go to a video tutorial on equations with
variables on both sides.
12
Answers to the problems: Expressions and Order of Operations 1. 11 − 𝑥
2. 3 (𝑛 + 10)
3. 4 (𝑛² − 5)
4. The product of twelve and a number
divided by four
5. a squared minus b to the fourth power
6. 169
7. 59
8. 118
9. −12
10. 209
11. 25
12. 3
13. −7
Properties of Real Numbers 1. F - Associative 2. E - Multiplicative Inverse 3. G - Commutative 4. H - Distributive 5. B - Additive Identity 6. G - Commutative 7. A - Multiplicative Property of Zero 8. D - Additive Inverse 9. J - Reflexive Property of Equality 10. K - Transitive Property of Equality
Solving Equations
1. 𝑘 = −19 2. 𝑥 = −15 3. 𝑦 = −28
4. 𝑛 = −1
2
5. 𝑘 = 4 6. 𝑔 = −1
7. 𝑚 = −5
3
8. 𝑥 = 2