Chapter 3: Problem 3
Find the equation of the line which passes through the point \((2,-3)\) and is parallel to the line \(y=\frac{3}{4} x+2\).
Short Answer
Expert verified
The equation is \(y = \frac{3}{4}x - \frac{9}{2}\).
Step by step solution
01
Identify the Slope of the Given Line
The given line has the equation \(y = \frac{3}{4}x + 2\). From this, we see that the slope \(m\) of this line is \(\frac{3}{4}\). Since we want to find a line parallel to this one, the parallel line will also have the same slope, \(\frac{3}{4}\).
02
Use the Point-Slope Form
To find the equation of a line, we can use the point-slope form given by \(y - y_1 = m(x - x_1)\), where \((x_1, y_1)\) is a point on the line and \(m\) is the slope. Here, we know \((x_1, y_1) = (2, -3)\) and \(m = \frac{3}{4}\).
03
Substitute the Point and Slope
Substitute the point \((2, -3)\) and slope \(\frac{3}{4}\) into the point-slope equation: \(y + 3 = \frac{3}{4}(x - 2)\).
04
Simplify the Equation
Distribute \(\frac{3}{4}\) into \((x - 2)\) to get \(y + 3 = \frac{3}{4}x - \frac{3}{2}\). Then, subtract 3 from both sides to isolate \(y\): \(y = \frac{3}{4}x - \frac{3}{2} - 3\). Simplifying the constant term gives: \(y = \frac{3}{4}x - \frac{9}{2}\).
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 way to express the equation of a line using its slope and y-intercept. It is generally written as \( y = mx + b \). Here, \( m \) is the slope of the line, which shows how steep the line is, and \( b \) is the y-intercept, which indicates where the line crosses the y-axis. For example, in the equation \( y = \frac{3}{4}x + 2 \), the slope \( m \) is \( \frac{3}{4} \) and the y-intercept \( b \) is 2. This equation tells us that for every 4 units we move horizontally, the line moves 3 units vertically. This form is particularly useful when you need to quickly sketch a graph or determine if two lines are parallel (by comparing their slopes). Additionally, slope-intercept form makes it simple to predict how changing \( m \) or \( b \) would transform the line on a graph.
Point-slope form
The point-slope form is another useful way to write the equation of a line. It is most helpful when you know a point on the line and the slope but not the y-intercept. The form is given by \( y - y_1 = m(x - x_1) \), where \( (x_1, y_1) \) is a known point and \( m \) is the slope of the line. This form allows direct input of these known values to establish an equation for the line. For the exercise, since the slope \( m \) is known to be \( \frac{3}{4} \) and the point \( (2, -3) \) is given, we can plug these into the point-slope form: * \( y + 3 = \frac{3}{4}(x - 2) \). By solving for \( y \), it becomes easier to convert this equation into the slope-intercept form, where it is often simpler to read and interpret the graphically.
Parallel lines
Parallel lines in a plane are lines that never intersect. This means they have the same slope, but different y-intercepts. The fact that parallel lines share the same slope is really crucial, as it simplifies finding equations for lines parallel to a given line. In our exercise, we were asked to find a line parallel to \( y = \frac{3}{4}x + 2 \). Knowing that parallel lines share the same slope, our new line must also have a slope of \( \frac{3}{4} \). By applying the point-slope form using the point \( (2, -3) \) and this slope, we establish the equation of our new line as \( y = \frac{3}{4}x - \frac{9}{2} \). The difference in the y-intercept from the original line is what keeps these two lines from intersecting, confirming their parallel nature.