The document explains the concept of slope as a measure of the steepness of a line connecting two points, outlining various formulas and methods to calculate it. It describes four types of slopes: positive, negative, zero, and undefined, as well as the slope-intercept form of a linear equation. Additionally, it provides examples and encourages reflection on the application of slope knowledge in real life.

1. What is Slope?
Algebra Grade 9
Ms. Warden

2. What Does Slope Mean?
Slope is a measure of the steepness of a line, or a
section of a line, connecting two points. In this
lesson, you will use several different formulas for
slope and learn how those formulas relate to the
steepness of a line.
The slope of a line is the ratio of the amount
that y increases as x increases some amount.
Slope tells you how steep a line is, or how
much y increases as x increases. The slope is
constant (the same) anywhere on the line.

3. Real Life Examples of Slope
What are some examples of slope that you can find in
your everyday life?

4. How Many Slopes Are There?
4 Different Slopes
Positive Slope Negative Slope
Zero Slope Undefined Slope

5. Slope-Intercept Form
y = mx + b
y = y-value for a point on the line
x = x-value for a point on the line
m = slope
b = y-intercept (where the line crosses the y axis)

6. How to Find Slope: Rise over Run

7. How to Find Slope: 2 Points on a Line

8. How to Find Slope: From an Equation
8x + 2y = 16 Move the 8x to the other side
2y = -8x + 16 Divide all terms by 2
y = -4x + 8 Equation is now in slope-intercept form
Linear equations are literal equations, which means that you can
solve for any one of the variables. In order to find the slope of a
line from an equation, you must first solve the given equation for y.
Please refer to the example below:
Slope = -4

9. Finding Y-Intercept
in Slope-Intercept Form
To find the y-intercept from slope-intercept form, you must have
one point that lies on the line, as well as the slope of the line.
Example:
If the point (0, 2) lies on a line with a slope of 4,
what is the y-intercept?
y = mx + b Begin with slope-intercept form
2 = (4)(0) + b Plug in the point values and slope
2 = 0 + b Solve for b
b = 2 y-intercept = 2

10. Lesson Reflection
1. Which of the methods for solving for slope is
most difficult for you? Why do you think that is?
2. How can you apply your knowledge of slope in
the real world?
3. Our next lesson will cover graphing linear
equations. Do you think that the information
you’ve learned in this class will help you graph
linear equations? Why?