Math 9 Exam Reviewer: Slope and Linear Equations

Vocabulary flashcards covering slope-intercept form, calculating slope using two points, types of slope, intercepts, and linear function word problems from Math 9 exam review notes.

Slope-Intercept Form

The linear equation form given by $y = mx + b$, where $m$ is the slope and $b$ is the y-intercept.

Slope ($m$)

The rate of change or steepness of a line, represented by $m$ in linear equations.

Y-Intercept ($b$)

The point where a line crosses the y-axis, represented as $b$ or as an ordered pair $(0, b)$, found by setting $x = 0$.

Slope Formula

The formula $m = \frac{y_2 - y_1}{x_2 - x_1}$ used to calculate the slope given two points, requiring consistent ordering of coordinates.

Positive Slope

A slope where the line goes UP from left to right (e.g., $y = 3x + 2$).

Negative Slope

A slope where the line goes DOWN from left to right (e.g., $y = -2x + 5$).

Zero Slope

The slope of a FLAT horizontal line (e.g., $y = 4$).

Undefined Slope

The slope of a VERTICAL line (e.g., $x = 3$).

X-Intercept

The point where a line crosses the x-axis, represented as an ordered pair $(x, 0)$, found by setting $y = 0$.

Intercepts Exam Trick

The rule 'X \rightarrow kill Y, Y \rightarrow kill X', which specifies setting $y = 0$ to find the x-intercept and setting $x = 0$ to find the y-intercept.

Rate of Change

In linear function word problems modeled by $y = mx + b$, the value represented by the slope $m$.

Starting Value

In linear function word problems modeled by $y = mx + b$, the initial value represented by the y-intercept $b$.