Like this study set? Create a free account to save it.

Sign up for an account

Already have a Quizlet account? .

Create an account

Linear equations in two variables

an equation that can be written in the for Ax + By = C, where A and B are not both 0.


a point where a graph intercepts the x-axis.


a pint where a graph intercepts the y-axis.

RULE: the y-intercept of y = mx + b

given an equation in the form y = mx + b, the coordinates of the y-intercept are (0, b).

RULE: horizontal lines and vertical lines

the graph of y = c, where c is a real number constant, is a horizontal line parallel to the x-axis with a y-intercept at (0, c).

the graph of x = c, where c is a real number constant, is a vertical line paralell to the y-axis with an x-intercept at (c, 0).


the ratio of the vertical change between any two points on a line to the horizontal change between those points.

RULES: graph of equations in slope-intercept form

the graph of an equation in the form y = mx + b (slope-intercept form) is a line with slope m and y-intercept (0, b). The following rules indicate how m affects the graph:

If m > 0, then the line slants upward from left to right

If m < 0, then the line slants downward from left to right.

The greater the absolute value of m, the steeper the lined

RULE: the slope formula

given two points (x₁, y₁) and (x₂, y₂), where x₂ ≠ x₁, the slope of the line connecting the two points is given by the formula
m = y₂-y₁/x₂-x₁

RULE: slope of horizontal and vertical lines

two points with different x-coordinates and the same y-coordinates (x₁, c) and (x₂, c) will form a horizontal line with slope 0 and equation y = c.

two points with the same x-coordinates and different y-coordinates (c, y₁) and (c, y₂) will form a vertical line with undefined slope and equation x = c.

RULE: parallel lines

the slopes of parallel lines are equal

RULE: perpendicular lines

the slope of a line perpendicular to a line with a slope of a/b is -b/a.

Linear inequality in two variables

an inequality that can be written in the form Ax + By > C, where the inequality could also be <, ≥ or ≤.


a set of ordered pairs


a relation in which each value in the domain is assigned to exactly one value in the range


a set containing initial values of a relation; its input values; first coordinates in ordered pairs.


a set containing all values that are paired to domain values in a relation; its output values; second coordinates in ordered pair.

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

Voice Recording