Podcast
Questions and Answers
Which equation represents a linear function?
Which equation represents a linear function?
What is the slope of the line represented by the equation $y = 2x + 5$?
What is the slope of the line represented by the equation $y = 2x + 5$?
Which of the following points lies on the line represented by the equation $y = 4x - 1$?
Which of the following points lies on the line represented by the equation $y = 4x - 1$?
What is the y-intercept of the line given by the equation $y = -3x + 6$?
What is the y-intercept of the line given by the equation $y = -3x + 6$?
Signup and view all the answers
What is the general form of a linear function?
What is the general form of a linear function?
Signup and view all the answers
If a linear function has a slope of $-2$ and passes through the point $(3, 4)$, what is the equation of the line?
If a linear function has a slope of $-2$ and passes through the point $(3, 4)$, what is the equation of the line?
Signup and view all the answers
What is the slope of the line represented by the equation $3x - 4y = 12$ when rewritten in slope-intercept form?
What is the slope of the line represented by the equation $3x - 4y = 12$ when rewritten in slope-intercept form?
Signup and view all the answers
A linear function is represented by the equation $y = mx + 7$. If the value of $m$ is halved, what is the new y-intercept if the original slope is $4$?
A linear function is represented by the equation $y = mx + 7$. If the value of $m$ is halved, what is the new y-intercept if the original slope is $4$?
Signup and view all the answers
If the function $f(x) = 5x - 3$ is translated 2 units up, what is the new equation?
If the function $f(x) = 5x - 3$ is translated 2 units up, what is the new equation?
Signup and view all the answers
Which of the following scenarios describes a linear function correctly?
Which of the following scenarios describes a linear function correctly?
Signup and view all the answers
Flashcards
Linear Function
Linear Function
A function whose graph is a straight line.
Elementary Function
Elementary Function
A basic function used to describe relationships between variables.
Freshman College
Freshman College
First year of college, often concerning fundamental math concepts.
Question
Question
Signup and view all the flashcards
Linear Function Question
Linear Function Question
Signup and view all the flashcards
Slope of a Linear Function
Slope of a Linear Function
Signup and view all the flashcards
Y-intercept of a Linear Function
Y-intercept of a Linear Function
Signup and view all the flashcards
How to Find the y-intercept?
How to Find the y-intercept?
Signup and view all the flashcards
How to Find the Slope?
How to Find the Slope?
Signup and view all the flashcards
Study Notes
- A linear function is a function whose graph is a straight line. It can be represented by the equation y = mx + b, where 'm' is the slope and 'b' is the y-intercept.
Key Characteristics of Linear Functions
-
The slope (m) represents the rate of change of y with respect to x. A positive slope indicates an upward trend, a negative slope a downward trend, and a zero slope a horizontal line.
-
The y-intercept (b) is the point where the line crosses the y-axis. It represents the value of y when x is zero.
-
The equation is of the first degree (the highest power of the variable is 1).
Graphing Linear Functions
-
To graph a linear function, two points are sufficient. Find two points that satisfy the equation (x, y) and plot them on a coordinate plane. Draw a straight line passing through these two points.
-
Alternatively, you can use the slope-intercept form (y = mx + b) directly: plot the y-intercept (0, b), then use the slope (m) to find a second point. Rise over run (m = rise/run) determines the change in y for a given change in x.
Finding the Equation of a Line
-
Given two points (x₁, y₁) and (x₂, y₂), the slope can be calculated as m = (y₂ - y₁)/(x₂ - x₁)
-
After finding the slope, use the point-slope form, y - y₁ = m(x - x₁), to find the equation. Substitute one of the points and the slope into this form.
Special Cases of Linear Functions
-
Horizontal lines: These have a slope of zero, and their equation is of the form y = b.
-
Vertical lines: These have an undefined slope (division by zero) and their equation is of the form x = a.
Applications of Linear Functions
- Many real-world situations involve linear relationships. Examples include:
- Calculating total cost (if there's a constant rate like cost per item).
- Determining distance traveled if speed is constant.
- Modeling growth or decay at a fixed rate.
Determining the Slope and Y-Intercept
-
Given an equation in the form y = mx + b: the slope is 'm', and the y-intercept is 'b'.
-
Sometimes an equation is given in a different form and needs to be rearranged to the slope-intercept form. For example, if you are given 2x + 3y = 6, rearrange to isolate 'y'.
Example Problems (Illustrative)
-
Find the slope and y-intercept of the line described by the equation 2x - 4y = 8.
-
Rearrange the equation to slope-intercept form (y = mx + b):
- 2x - 8 = 4y
- y = (1/2)x -2
-
The slope is 1/2 and the y-intercept is -2.
-
-
Find the equation of the line passing through the points (3, 1) and (-1, 5).
- Calculate the slope: m = (5 - 1) / (-1 - 3) = -1.
- Use the point-slope form: y - 1 = -1(x - 3)
- Simplify to get the equation: y = -x + 4
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Explore the key characteristics of linear functions, including slope and y-intercept. Learn how to graph these functions using two points and the slope-intercept form. Test your understanding of the concepts applicable to linear equations.