Chapter 5: Problem 36
Sketch the graph of the line satisfying the given conditions. Passing through \((3,2)\) with slope 2
Short Answer
Expert verified
The equation of the line is \( y = 2x - 4 \).
Step by step solution
01
- Identify the slope-intercept form
The slope-intercept form of a line is given by the equation: \[ y = mx + b \] where \( m \) is the slope and \( b \) is the y-intercept. The given slope is 2.
02
- Use the point to find the y-intercept
Substitute the given point \((3, 2)\) and the slope \( m = 2 \) into the slope-intercept form equation to find \( b \).Starting with \[ y = mx + b \]Substitute \( y = 2 \), \( x = 3 \), and \( m = 2 \):\[ 2 = 2(3) + b \]Simplify:\[ 2 = 6 + b \]Solve for \( b \):\[ b = 2 - 6 \]\[ b = -4 \]Therefore, the y-intercept \( b \) is -4.
03
- Write the equation of the line
With the slope \( m = 2 \) and the y-intercept \( b = -4 \), the equation of the line is:\[ y = 2x - 4 \]
04
- Plot the line
To sketch the graph, start by plotting the y-intercept \( (0, -4) \).Next, use the slope to find another point. The slope \( 2 \) means a rise of 2 units for every run of 1 unit. From \( (0, -4) \), move up 2 units and right 1 unit to plot \( (1, -2) \).Finally, draw a straight line through these points.
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 of a linear equation is a fundamental concept in graphing lines. The formula is expressed as: \[ y = mx + b \] Where:
The slope-intercept form is particularly useful because:
- \(m\): This is the slope of the line. It indicates how steep the line is. The slope tells you how much \(y\) changes for a change in \(x\).
- \(b\): This represents the y-intercept of the line. It is the point where the line crosses the y-axis.
The slope-intercept form is particularly useful because:
- It makes it easy to graph the line just by knowing the slope and y-intercept.
- It allows for quick identification of key features of the graph.
finding y-intercept
Finding the y-intercept \(b\) is critical as it gives you one of the key points to start your graph. You can find \(b\) by substituting a known point on the line and the slope \(m\) into the slope-intercept form equation.
For the given problem, we substitute \((3, 2)\) and the slope \(m = 2\) using the equation below:
\[ y = mx + b \]
\[ 2 = 2(3) + b \]
\[ 2 = 6 + b \]
The next step is to isolate \(b\) by subtracting 6 from both sides:
\[ b = 2 - 6 \]
\[ b = -4 \]
Thus, the y-intercept \(b\) is -4. This is the point where the line crosses the y-axis, and it helps in plotting the graph accurately.
For the given problem, we substitute \((3, 2)\) and the slope \(m = 2\) using the equation below:
\[ y = mx + b \]
\[ 2 = 2(3) + b \]
\[ 2 = 6 + b \]
The next step is to isolate \(b\) by subtracting 6 from both sides:
\[ b = 2 - 6 \]
\[ b = -4 \]
Thus, the y-intercept \(b\) is -4. This is the point where the line crosses the y-axis, and it helps in plotting the graph accurately.
plotting points
Plotting points is the final step to graphing a linear equation. Start with the y-intercept you found earlier, which in this case is \( (0, -4) \). From here, use the slope to plot additional points.
For the slope \( 2 \), it indicates a rise of 2 units for every run of 1 unit. So, starting from \( (0, -4) \):
For the slope \( 2 \), it indicates a rise of 2 units for every run of 1 unit. So, starting from \( (0, -4) \):
- Move up 2 units
- Move right 1 unit to land at the next point \( (1, -2) \)
- Up 2 units to get \( -2 + 2 = 0 \)
- Right 1 unit to get \( 1 + 1 = 2 \)