Chapter 1: Problem 10
Why is it not possible to write a slope-intercept form of the equation of the line through the points \((12,6)\) and \((12,-2) ?\)
Short Answer
Expert verified
The line is vertical, so it lacks a defined slope for slope-intercept form.
Step by step solution
01
Identify the Points
The given points are \((12, 6)\) and \((12, -2)\). We need to find the slope between them.
02
Calculate the Slope
The formula for slope is \( m = \frac{y_2 - y_1}{x_2 - x_1} \). Plug the coordinates into the formula: \( m = \frac{-2 - 6}{12 - 12} = \frac{-8}{0} \).
03
Interpret the Undefined Slope
Since division by zero is undefined, a slope of \(\frac{-8}{0}\) means the slope is undefined. This occurs when a line is vertical.
04
Explain the Slope-Intercept Form
The slope-intercept form of a line is given by \( y = mx + b \), where \( m \) is the slope and \( b \) is the y-intercept. Vertical lines cannot have this form because they don't have a defined slope.
05
Conclude the Explanation
Thus, it is not possible to express the equation of a line through these points in slope-intercept form since the line is vertical. Vertical lines are expressed in the form \( x = k \), where \( k \) is the constant x-coordinate for any point on the line.
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Slope-Intercept Form
The slope-intercept form is a useful way to describe a line with a simple equation. This form is written as \( y = mx + b \), where:
- \( m \) represents the slope of the line
- \( b \) is the y-intercept, the point where the line crosses the y-axis
Undefined Slope
An undefined slope occurs when looking at vertical lines. To calculate the slope, use the formula \( m = \frac{y_2 - y_1}{x_2 - x_1} \). If you find yourself dividing by zero, the slope is undefined. For example, in the exercise, a vertical line is between the points \((12, 6)\) and \((12, -2)\). Both x-coordinates are the same, leading to division by zero: \( m = \frac{-8}{0} \). Since the slope is undefined, it indicates a vertical line. Such vertical lines rise straight up and down, unable to slant or have a slope, making it impossible to fit them into a standard slope-intercept form.
Equation of a Line
An equation of a line tells us the relationship between the x and y coordinates along that line. The most common form is the slope-intercept form \( y = mx + b \), readily showing slope and y-intercept. However, vertical lines are best expressed differently. When a line is vertical, every point on it has the same x-coordinate. Therefore, the equation of such a line is in the form \( x = k \), where \( k \) is the constant x value. In the exercise, the equation for the line through points \((12, 6)\) and \((12, -2)\) is simply \( x = 12 \). This equation reflects the unchanging nature of the x-value along the vertical line.
Division by Zero
Division by zero is a mathematical operation that can't be completed, as it is undefined. Consider it as trying to divide a given number among no groups, resulting in an undefined state. In slope calculations, particularly in the basic formula \( m = \frac{y_2 - y_1}{x_2 - x_1} \), there can be an attempt to divide by zero when the x-values are the same. This leads to an undefined slope, signaling a vertical line. Beware of division by zero, as it indicates scenarios that traditional methods can't handle, such as the determination of slope for vertical lines. It's a significant concept to remember when analyzing and plotting lines.