Algebra 1 Review:

1.1 Expressions and Formulas

Objectives:1) Use order of operations to evaluate

expressions 2) Use formulas

Order of Operations

Why? Because a numerical expression must have one value, so we can all arrive at the same answer.

PEMDAS

Please excuse my dear aunt sally

Order of Operations

Step One: Evaluate expression inside grouping symbols (parenthesis)

Step Two: Evaluate all powers Step Three: Do all multiplications

and/or divisions from left to right. Step Four: Do all additions and/or

subtractions from left to right.

P E M D A S

Order of Operations

Practice: Evaluate each expression

a.

b.

c.

d.

5]3)410(2[ 2

]3)27(3384[ 3

4

)229(16

2)48(644

Evaluate an Expression

Vocabulary: A variable is a symbol, usually a letter, that is

used to represent unknown quantities.

Expressions that contain at least one variable are called algebraic expressions.

Evaluate an Expression

1) Evaluate if x=8 and y=1.5

2) Evaluate if a=2, b=-4, and c=-3

)(2 yxyx

5

22

3

c

bca

1.2 Properties of Real Numbers

Objective: Classify real numbers and use the properties of real numbers to evaluate expressions.

Real Numbers

All of the numbers that you use in everyday life are real numbers

Each real number corresponds to exactly one point on the number line, and every point on the number line represents exactly one real number.

Rational vs. Irrational

Rational NumberCan be expressed as a

ratio , where m and n

are integers and n is not zero. The decimal form of a rational number is either a terminating or repeating decimal.

1.9, 2.575757…, -3, ,

Irrational Number

A real number that is not rational. The decimal form of an irrational number neither terminates nor repeats.

, , 0.010010001…

n

m

546

1

Classify Real Numbers

REAL NUMBERS

IrrationalsRationals

Integers

Whole

Natural

Natural {1, 2, 3, 4, 5,…}

Whole {0, 1, 2, 3, 4, 5,…}

Integers {…-3, -2, -1, 0, 1, 2, 3…}

Practice

Name the sets of numbers to which each number belongs.

a. b. 9.99999

c. d. -23.3

e.

3

2

6

100

Properties of Real Numbers

Property

Commutative

Associative

Identity

Inverse

Distributive

Addition

a + b = b + a

(a + b) +c = a + (b + c)

a + 0 = 0 + a

a + -a = 0 = -a + a

Multiplication

abba

)()( cbacba

aaa 11

If ,0a then aaa

a 1

11

a(b+c)=ab+ac and (b+c)a=ba+ca

Practice

Name the property illustrated by each equation:

a)

b)

c) (2+14)+3=3+(2+14)

d) -6xy + 0 = -6xy

)254(325)43( 3)52(3532

Simplify each expression

1. 7a + 3b – 4a – 5b

2. 3(15x – 9y) + 5(4y – x)

3. 7(0.2p + 0.3q) + 0.6(0.8x-6y)

HOMEWORK!!!!!

Page 47-48 #11-24 all

Get your syllabus signed and returned

Binder check next week! It must include all homework, notes, and class handouts to receive full credit!