Mathematics
Grade 8
15 min
Find the slope of an equation
Find the slope of an equation
Tutorial Preview
1
Introduction & Learning Objectives
Learning Objectives
Define slope as the rate of change in a linear relationship.
Calculate the slope of a line given two points on the line.
Identify the slope of a line from its equation in slope-intercept form (y = mx + b).
Rearrange a linear equation from standard form (Ax + By = C) into slope-intercept form to find its slope.
Interpret the meaning of positive, negative, zero, and undefined slopes.
Apply the concept of slope to real-world scenarios.
Have you ever seen a ramp or a hill? ⛰️ How would you describe how steep it is? That 'steepness' is exactly what we're going to measure in math!
In this lesson, you'll learn how to find the 'slope' of a line, which tells us how steep it is and in what direction it's going. Understanding slop...
2
Key Concepts & Vocabulary
TermDefinitionExample
SlopeSlope is a measure of the steepness and direction of a line. It describes how much the vertical distance (rise) changes for every unit of horizontal distance (run).A road sign indicating a '6% grade' means the road rises 6 feet for every 100 feet horizontally, so its slope is 6/100.
Linear EquationAn equation whose graph is a straight line. It represents a relationship where the rate of change (slope) is constant.y = 2x + 3 is a linear equation. When graphed, it forms a straight line.
RiseThe vertical change between two points on a line. It's the change in the y-coordinates.If a point moves from y=2 to y=5, the rise is 3 units.
RunThe horizontal change between two points on a line. It's the change in the x-coordinates.If a point moves from x=...
3
Core Formulas
Slope Formula (from two points)
$$m = \frac{y_2 - y_1}{x_2 - x_1}$$
Use this formula to calculate the slope (m) of a line when you are given the coordinates of two distinct points on the line, $(x_1, y_1)$ and $(x_2, y_2)$. Remember that $x_2 - x_1$ cannot be zero.
Slope from Slope-Intercept Form
$$y = mx + b$$
When a linear equation is written in slope-intercept form, the coefficient 'm' directly represents the slope of the line. 'b' represents the y-intercept.
Slope from Standard Form
To find the slope from $Ax + By = C$, first rearrange it to $y = mx + b$. This means isolating 'y': $By = -Ax + C \Rightarrow y = \frac{-A}{B}x + \frac{C}{B}$. The slope is $m = \frac{-A}{B}$.
If your linear equation is in standard form, you must first so...
5 more steps in this tutorial
Sign up free to access the complete tutorial with worked examples and practice.
Sign Up Free to ContinueSample Practice Questions
Challenging
The line passing through points (4, k) and (6, 11) has a slope of 3. What is the value of k?
A.2
B.17
C.8
D.5
Challenging
What is the slope of a line that is parallel to the line given by the equation 4x + 2y = 9?
A.2
B.-2
C.-1/2
D.4
Challenging
Find the slope of the line represented by the equation (1/2)x + (1/3)y = 2.
A.1/2
B.2/3
C.-2/3
D.-3/2
Want to practice and check your answers?
Sign up to access all questions with instant feedback, explanations, and progress tracking.
Start Practicing Free