6 Expressions Flashcards
technique
Combining like terms
match variables (i.e. x or x^2 or y) with like variables
key formula: expansion & factoring
(a - b)^2
a^2 - 2ab + b^2
key formula: expansion & factoring
a^2 - 2ab + b^2 =
(a - b)^2
key formula: expansion & factoring
a^2 - b^2 =
(a+b)(a-b)
technique
in combining fractions, find
the least common multiple of the denominators
example: combining fractions
what is the common denominator of
(1/x+2) + (2/x-2)?
the product of the two denominators, (x+2)(x-2)
confusing note
what is the difference between (1/2)/3 and 1/(2/3)?
(1/2)/3 = 1/6
1/(2/3) = 3/2
key formula: flipping(dividing) fractions
a/(b/c)
ac/b
key formula: flipping(dividing) fractions
(a/b)/c
a/bc
example: splitting fractions
simplify (30+c)/6
(30+c)/6 = 30/6 + c/6 = 5+ c/6
define
what is an expression?
combinations of numbers and variables
a sentence with a minimum of two numbers/variables and at least one math operation in it.
example
what is an example of an expression?
expression: 4x^2 + 9
WHEREAS
equation: 4x^2 + 9 = 25
recognizing type of questions: constructing models
constructing model questions require:
represent real-life quantities as expressions, equations, and graphs; must combine what you’ve learned from the first 6 chapters
