pre algebra Flashcards
natural #’s
1, 2, 3, ,4 ….
whole #’s
0, 1, 2, 3, …..
standard form
322
place value
position of digit in a number is called
period
group of three digits is called
expanded form
300 + 20 + 2
words used when adding
total, sum
words used when subtracting
difference
words used when multiplying
product, factor, of
words used when dividing
quotient
in words
three hundred twenty-two
commutative property
only in addition & multiplication
order of addition does not matter
4 + 8 = 8 + 4
9 * 2 = 2 * 9
associative property
only in addition & multiplication
grouping does not matter
(3+6) + 2 = 3 + (6+2)
(2 * 3) * 4 = 2 * (3 * 4)
multiplication property of zero
a * 0 = 0
multiplication property of 1
a * 1 = a
distributive property
6(4 + 5) = 6(4) + 6(5)
rounding
does not matter unless stated
area
a = length * width
don’t forget to square it!!
perimeter
sum of sides (length) added together
addends
’s that are being added
minuend
# you are subtracting from first # in problem
subtrahend
# you are subtracting after the subtraction sign
divisor
# in front of division bracket # after the division sign denominator
division property of 1
the quotient of any # (except 0) and that same # is 1
the quotient of any # and 1 is that same #
division property of zero
quotient of 0 and any # (except 0) is 0
quotient of any # and 0 is not a # - undefined
if 0 is in front of division bracket, 0 after division sign or 0 is the denominator
exponent
little number after base
number of times base is a factor
Order of Operations
~ alway work left to right ~
P: grouping symbols first E: exponents M: multiply D: divide A: add S: subtract
variable
a letter that represents a number and can change
constant
stays the same
algebraic expression
combination of operations on variables and #s
all we do is evaluate expressions; exponents have to be the same to combine, coefficients can be different then it’s simplified
equations
expression = expression
we solve
negative #s
numbers less than 0
symbol is -
integers
…, -3, -2, -1, 0, 1, 2, , …3
>
is greater than
is less than
absolute value
number’s distance from 0 on the # line
the symbol is | |
always positive
opposites
two numbers that are the same distance from 0 on the # line but are on opposite sides of 0
sign stays the same
adding two number that have the same sign
change sign
adding different signs. subtract the smaller # from the larger # and keep sign of larger
opposite of a negative
is a positive
subtracting negatives
is adding and keeping the - sign
positive integers
if signs are the same
multiplying & dividing
negative integers
if signs are different
multiplying & dividing
addition property of equality
a = b
a + c = b + c
a - c = b - c
multiplication property of equality
a = b
a * c = b * c
a / c = b / c
average
sum of #s divided by # of #s
signed #s
positive, negative and 0
numerical coefficient
number factor of a variable term
term
addends of an algebraic expression
like terms
exact same terms, can have different numerical coefficients
us to meter
10oz estimates 28 g 2.2 lbs estimates 1 kg 1 qt estimates 1 L 1 yd estimates 1 m 6.2 mi estimates 10 km
expressions
combine like terms, there is no =
variables with their components have to be the same, coefficients can be different
ratios
the quotient of two quantities
rates
compare different kinds of quantities
unit rate
a rate with a denominator of 1
proportions
states that two ratios are equal
cross multiply to see if true
square of a #
the # times itself
square root
reverse process of squaring
uses a radical sign
pythagorean theorem
length of the legs of right triangle equal the hypotenuse
all squared
congruent triangles
same shape and same size
similar triangles
same shape but not necessarily the same size
percent proportion
amount / base = percent
precent of increase
equals amount of increase / original amount
precent of decrease
equals amount of decrease / original amount
sales tax
equals tax rate * purchase price
total price
equals purchase price + sales tax
commission
equals commission rate * sale
amount of discount
equals discount rate * original price
sale price
equals original price - amount of decrease
simple interest
I = P * R * T
