8th grade common core math vocabulary.

transformation
moving a shape so that it is in a different position, but still has the same size, area, angles and line lengths

pre-image
the original image before transformation

image
a figure resulting from a transformation

rotation
a transformation made by rotating (turning or spinning) a figure around a given point

reflection
a transformation created by reflecting (flipping) an image over a line

translation
a transformation created by sliding an object

dilation
a transformation created proportionally by enlarging or reducing a figure

congruent
having the same size and shape

exterior angles
an angle formed outside a polygon by extending one of its sides

plane
a flat, 2D surface that goes in all directions forever

transversal
a line that intersects (crosses) two or more lines in a given plane

proof
a convincing demonstration that a mathematical statement is true

hypotenuse
the side opposite the right angle - it is also the longest side of a right triangle

Pythagorean Theorem
in a right triangle the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the legs A²+B²=C²

cone volume
the number of cubic units needed to fill a cone

cylinder volume
the number of cubic units needed to fill a cylinder

sphere volume
the number of cubic units needed to fill a sphere

rational number
a number that can be expressed as a ratio (fraction) of two integers - terminating and repeating decimals are considered rational

irrational number
a number that can NOT be expressed as a ratio of two integers or as a repeating or terminating decimal - Pi or any square root of an imperfect square are considered irrational

radical symbol
the symbol used to represent the non-negative square root of a number

square root
one of two equal factors (multiplication) of a number - it is the side of a square

cubed root
one of three equal factors (multiplication) of a number - it is the side of a cube

scientific notation
a method of writing very large (34,200,000) or very small (0.0000029) numbers using powers of 10

linear function
a function (equation) whose graph is a straight line

non-linear function
a function (equation) whose graph is NOT a straight line

function (equation or rule)
an input-output relationship that has exactly one output (y-value) for each input (x-value)

scatter plot
a graph with points plotted to show a possible relationship between two sets of data

bivariate measurement
involves the analysis of two variables for the purpose of determining a relationship

outlier
a value much greater or much less than the others in a set of data - any data point 1.5 times the interquartile range away from the 1st quartile (lower quartile) or 3rd quartile (upper quartile)

line of best fit
a straight line that comes closest to the points on a scatter plot - having an equal number of points above and below the line

linear equation
an equation that makes a straight line when it is graphed - also called a linear function

slope
a measure of the steepness of a line on a graph - m - rise over run - pattern of the y-outputs

intercepts
points where a line crosses the x-axis and y-axis

slope-intercept form
a linear equation written in the form y = mx + b, where m represents slope and b represent the y-intercept

coefficient
the number that is multiplied by (in front of) the variable in an algebraic expression

variable
a symbol for an unknown number - usually expressed as a letter