Chapter 11: Problem 52
Find an equation of the line satisfying the given conditions. Containing the points \((2,3)\) and \((4,-5)\)
Short Answer
Expert verified
y = -4x + 11
Step by step solution
01
Identify the coordinates
The problem provides two points: \(2, 3\) and \(4, -5\). Label these points as \(x_1, y_1\) = \(2, 3\) and \(x_2, y_2\) = \(4, -5\).
02
Calculate the slope
Use the slope formula \[ m = \frac{y_2 - y_1}{x_2 - x_1} \] to find the slope of the line. Substitute the given points into the equation: \[ m = \frac{-5 - 3}{4 - 2} = \frac{-8}{2} = -4 \]
03
Use the point-slope form
The point-slope form of the equation of a line is \[ y - y_1 = m (x - x_1) \]. Using the point \(2, 3\) and the calculated slope \(m = -4\), substitute into the equation: \[ y - 3 = -4 (x - 2) \]
04
Simplify to slope-intercept form
Distribute and simplify the equation to get it into slope-intercept form \(y = mx + b\): \[ y - 3 = -4x + 8 \] \[ y = -4x + 8 + 3 \] \[ y = -4x + 11 \]
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 Calculation
To start understanding the equation of a line, it's essential to grasp the concept of slope. Slope indicates how steep a line is and is calculated using the coordinates of two points on the line.
The formula for slope calculation is written as: \[ m = \frac{y_2 - y_1}{x_2 - x_1} \]
Here, \(m\) represents the slope, and \(x_1, y_1\) and \(x_2, y_2\) are the coordinates of the two points.
Let's go through the steps given in the problem:
The formula for slope calculation is written as: \[ m = \frac{y_2 - y_1}{x_2 - x_1} \]
Here, \(m\) represents the slope, and \(x_1, y_1\) and \(x_2, y_2\) are the coordinates of the two points.
Let's go through the steps given in the problem:
- Identify the coordinates. We have \( (2,3) \) and \( (4,-5) \).
- Substitute these points into the formula.
\[ m = \frac{-5 - 3}{4 - 2} = \frac{-8}{2} = -4 \]
As shown, the slope of the line is \( -4\).
This negative slope signifies that the line is descending.
Point-Slope Form
The point-slope form of a line's equation is handy. This form uses a known point and the slope to describe the whole line. The formula for point-slope form is:
\[ y - y_1 = m (x - x_1) \]
Here, \( y_1 \) and \( x_1 \) are the coordinates of the given point, and \( m \) is the slope.
Using the given point \( (2,3) \) and our calculated slope \( -4 \), we substitute these into the formula:
\[ y - y_1 = m (x - x_1) \]
Here, \( y_1 \) and \( x_1 \) are the coordinates of the given point, and \( m \) is the slope.
Using the given point \( (2,3) \) and our calculated slope \( -4 \), we substitute these into the formula:
- \[ y - 3 = -4 (x - 2) \]
By doing so, we have mapped out the line using this specific point and the slope.
Slope-Intercept Form
The slope-intercept form is a standard way to represent a line in mathematics. It is written as:
\[ y = mx + b \]
Where \( m \) is the slope and \( b \) is the y-intercept (the point where the line crosses the y-axis).
To convert our point-slope form equation to slope-intercept form, simplify it as follows:
\[ y = mx + b \]
Where \( m \) is the slope and \( b \) is the y-intercept (the point where the line crosses the y-axis).
To convert our point-slope form equation to slope-intercept form, simplify it as follows:
- Starting with:
\[ y - 3 = -4 (x - 2) \] - Distribute the slope:
\[ y - 3 = -4x + 8 \] - Isolate \( y \):
\[ y = -4x + 8 + 3 \]
\[ y = -4x + 11 \]