1. Miss Rodriguez and Miss Eggleton Section 1.1/1.2 Real Numbers and Number Operations Algebraic Expressions and Models

2. Important Terms: Origin- point labeled 0 Whole Numbers- #’s that are not negative, decimals, or fractions Integers- same as whole numbers, but can be negative Rational Numbers- #’s that can be written as the ratio of two integers Irrational Numbers- real numbers that are not rational Graph- point on a number line that corresponds to a real # Coordinate- # that corresponds to a point on a number line Opposite- inverse of any # ( a becomes –a) Reciprocal- a becomes 1 /a

3. PropertyAdditionMultiplication Closurea+b is a real #ab is a real # Commutativea+b=b+aab=ba Associative(a+b)+c=a+(b+c)ab(c)=a(bc) Identitya+0=a, 0+a+aa*1=a, 1*a=a Inversea+(-a)=0a*1/a=1. a≠0 Distributivea(b+c)= ab+ac

4. Important Terms A variable is a letter that is used to represent one or more numbers. Any number that is used to replace a variable is a value of the variable. An expression involving variables is called an algebraic expression. When the variables in an algebraic expression are replaced by numbers, you are evaluating the expression, and the result is called the value of the expression. An expression that represents a real life situation is a mathematical model. Numerical expression- consists of numbers, operations, and grouping symbols

5. Order of Operations: First, do operations that occur within grouping symbols Next, evaluate powers Then, do multiplication and divisions from left to right Finally, do addition and subtraction from left to right PEMDAS

6. Extra Information Ex. 2x+3 The parts added together, 2x and 3, are called terms. Ex. 2 = 2*2*2*2*2 2 is the base 5 is the exponent the expression is a power When a term is the product of a number and a power of a variable, such as 2x or 4x, the number is the coefficient of the power. Terms such as 3x and -5x are like terms because they have the same variable part. Constant terms such as -4 and 2, are also like term. Two algebraic expressions are equivalent if they have the same value for all values of their variables. Ex. 7x+4x and 11x are equivalent, as are expressions 5x-(6x+y) and -x-y. A statement such as 7x+4x=11x that equates two equivalent expression is called an identity. 5 3