# Algebra Chapter 4 Graphing Linear Equations

## 25 terms · Flashcards for Algebra 1 chapter 4 Graphing Linear Equations

One of 4 regions of the coordinate plane formed by the intersection of the x- and y-axes.

### abscissa

The x-coordinate of an ordered pair.

### ordinate

The y-coordinate of an ordered pair.

### ordered pair

Describes a location on the coordinate plane, with the x-coordinate listed first and the y-coordinate listed second.

### origin

Ordered pair (0,0); the place where the axes in a coordinate plane meet.

### Ax + By = C

Standard form of a linear equation, where A, B, and C represent constant numbers and x and y represent variables.

### Table of Values Graphing Method

One way to graph a function; first find some x-values in the domain, and then calculate the y-values using the function rule; points can then be plotted and connected.

### x-intercept

The place where the graph of a relation touches or crosses the x-axis; the y-value is always 0.

### y-intercept

The place where the graph of a relation touches or crosses the y-axis; the x-value is always 0.

### Intercepts Graphing Method

One way to graph a function; find the x-intercept (set y = 0 and solve) and the y-intercept (set x = 0 and solve); plot the intercepts and connect.

### y = mx + b

The slope-intercept form of a linear equation, where m represents slope and b represents y-intercept.

### Slope-Intercept Graphing Method

Put a linear equation in slope-intercept form (y = mx + b); plot the y-intercept; use the slope ratio to find other points relative to the y-intercept (make slope a fraction - numerator is change in y (up or down), denominator is change in x (left or right)).,

### slope

The ratio of change in y-value (vertical) to change in x-value (horizontal) between two points on a line.

### slope formula

Given two points (x1, y1) and (x2, y2), slope is found using the formula m = (y2 - y1)/(x2 - x1), or delta y over delta x.

### undefined slope

The slope of a vertical line (cannot be found because it would force a division by 0, undefined in mathematics)

### positive slope

The slope of a line that increases as x-values increase (points go up left to right).

### negative slope

The slope of a line that decreases as x-values increase (points go down left to right).

### zero slope

The slope of a horizontal line (the change in y-values is 0).

### constant of variation

The constant applied to input values to create the output values in a direct variation; given y = ax is a direct variation, then a is the constant of variation.

### y-intercept = 0

One way to determine if a linear equation is a direct variation.

### f(x) notation

Function notation where f is the name of the function and x is the input; for example if f(x) = x + 2, then f(3) = 3 + 2 = 5.

### domain

The set of inputs for a relation.

### range

The set of outputs for a relation.

### x = a, a is a constant

Graph of a vertical line; for example, x = 5 is a vertical line that goes through point (5, 0); it has an undefined slope

### y = a, a is a constant

Graph of a horizontal line; for example, y = 5 is a horizontal line that goes through point (0, 5); it has a slope of 0