###
acute triangle

triangle with all angles less than 90 degrees

###
algebraic expression

numbers, symbols, and variables

###
area

space inside a 2D figure

###
bar graph

uses bars to compare data

###
base

the bottom of a figure

###
circumference

distance around a circle

###
congruent

same size and shape

###
cubed

the third power (exponent of 3)

###
denominator

bottom of fraction

###
diameter

distance across a circle

###
dilation

a larger or smaller version of a figure

###
equation

a math sentence with an = sign

###
equilateral triangle

triangle where all sides are equal length

###
equivalent fractions

two equal fractions

###
experimental probability

chances based on results of experiment

###
exponent

tells how many times to multiply a number

###
expression

collection of numbers, symbols, and/or variables

###
factor

a number that can be multiplied to make another number

###
frequency table

uses tallys to record how often something occurs

###
GCF

greatest common factor

###
histogram

uses bars to compare intervals of numbers

###
inequality

one expression in greater than or less than another

###
integers

positive whole numbers and opposites

###
isosceles triangle

two sides are the same

###
LCM

least common multiple - least common number that two numbers are factors of

###
line graph

best type of graph for changes over time

###
line plot

uses x's to show how often a data item occurs

###
mean

the average of a group of numbers - add numbers and divide by how many numbers

###
median

the middle number in a set of numbers

###
mode

the most common in a set of numbers

###
numerator

the top of a fraction

###
obtuse triangle

a triangle with one angle larger than 90 degrees

###
order of operations

parenthesis, exponents, multiply and divide, add and subtract

###
outlier

a value that is much greater or much less than the rest of the numbers

###
parallel

never intersect

###
perpendicular

intersect and form a right angle

###
parallelogram

quadrilateral with 2 pairs of parallel sides

###
percent

a ratio out of 100

###
perimeter

the distance around a polygon

###
plane

a flat surface

###
polygon

closed figure made of at least 3 line segments

###
prime factorization

writing composite numbers and product of primes

###
prime number

number that has only 2 factors (1 and itself)

###
probability

measuring how likely something is to occur

###
proportion

2 equal ratios

###
quadrilateral

having 4 sides

###
quotient

the answer to a division problem

###
radius

halfway across circle; from center to edge of circle

###
range

highest value minus lowest value

###
ratio

comparing 2 numbers by division

###
reflection

a mirror image of a figure

###
right triangle

triangle with a right angle

###
rotation

turning a figure around a point

###
rule

a procedure for creating a pattern in a series of numbers

###
scalene triangle

all sides different length in a triangle

###
sector

a part of a circle

###
similar figures

same shape, but a larger or smaller version; sides form a proportion

###
squared

number to the second power (times itself)

###
surface area

area of the outside of a 3D figure

###
theoretical probability

what should happen based on possible outcomes

###
translation

moving (or sliding) a figure along a straight path

###
trial

performing an experiment

###
variable

letter used to represent an unknown quantity

###
volume

space inside a 3D figure

###
vertex

corner of a 2D or 3D figure where 2 lines meet

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