1.2 Algebraic Expressions

PROPERTIES - REVIEW  a+b=b+a or a∙b=b·a  a+(b+c) = (a+b)+c a ∙ (b ∙ c) = (a ∙ b) ∙ c a ∙ (b ∙ c) = (a ∙ b) ∙ c  a+0=a  a ∙1=a  a+-a = 0  a ∙(1/a) = 1  a(b + c) = ab + ac COMMUTATIVE  ASSOCIATIVE  IDENTITY  INVERSE  DISTRIBUTIVE 

PROPERTIES cont’d SUBTRACTION  DIVISION  OPP of SUM  OPP of DIFF  OPP of PRODUCT   a – b = a + (-b)  –(a+b) = – a + (– b)  –(a – b) = –a + b = b – a  – (–a) = a

ALGEBRAIC EXPRESSIONS EX - Expressions

ALGEBRAIC EXPRESSIONS EX – Formulas Evaluate for x = 5 and y = -3

ALGEBRAIC EXPRESSIONS Simplify ALWAYS WRITE VARIABLES IN ALPHABETICAL ORDER GOINGS FROM LEFT TO RIGHT

FIND PERIMETER Perimeter = add all sides Perimeter = add all sides 3x + 2x + (3x – y – 1 ) + y + (y+1) + (2x - y) 3x + 2x + (3x – y – 1 ) + y + (y+1) + (2x - y) 10x 10x 3x 2x y+1 y NEED THESE SIDES 3x – (y+1) = 3x – y – 1 2x - y