### axis of symmetry

line that divides a graph into two halves that are mirror images

### nonlinear relationship

relationship between two variables for which a linear model is not a good fit

### parabola

shape of the graph of a quadratic function

### parent function

function of a certain family type that has the simplest algebraic rule

### quadratic function

function, where $a$, $b$, and $c$ are real numbers and $a\neq0$, written in the form:

$f(x) = ax^2 + bx + c$

### quadratic relationship

nonlinear relationship between two variables for which a quadratic function is an appropriate model

### regression

mathematical process for determining the equation of the graph that best models a set of data

### scatterplot

data display consisting of the graph of a set of ordered pairs

### standard form of a quadratic function

quadratic equation, where $a$, $b$, and $c$ are real numbers and $a\neq0$, written in the form:

$f(x) = ax^2 + bx + c$

### vertex

highest or lowest point on a parabola

### vertex form of a quadratic function

quadratic equation , where $a$, $h$, and $k$ are real numbers and $(h, k)$ is the vertex of the parabola, written in the form:

$f(x) = a(x-h)^2+k$