Parallel Line Equation: Find It Easily!

by Viktoria Ivanova 40 views

Have you ever wondered how to find the equation of a line that runs parallel to another, while also passing through a specific point? It might sound tricky, but don't worry, guys! It's actually a pretty straightforward process once you break it down. In this article, we'll tackle the challenge of finding the equation of a line parallel to $y = - rac{3}{2}x - 1$ and passing through the point (4, 6). We'll go through each step in detail, making sure you understand the underlying concepts along the way. So, grab your pencils and let's dive in!

Understanding Parallel Lines

Before we jump into the calculations, let's make sure we're all on the same page about what parallel lines are. Parallel lines are lines that run in the same direction and never intersect. Think of railroad tracks – they run side by side and maintain a constant distance from each other. The most important characteristic of parallel lines for our purposes is that they have the same slope. The slope of a line tells us how steep it is, and whether it's going uphill or downhill. If two lines have the same slope, they're going in the same direction, hence, they are parallel.

In the equation $y = mx + b$, which is the slope-intercept form of a linear equation, m represents the slope and b represents the y-intercept (the point where the line crosses the y-axis). So, when we look at the equation $y = - rac{3}{2}x - 1$, we can immediately identify that the slope of this line is $- rac{3}{2}$. This is crucial information because any line parallel to this one will also have a slope of $- rac{3}{2}$. This understanding forms the foundation for finding the equation of our desired parallel line. We know the direction it needs to go, now we just need to figure out its specific position on the graph.

To further illustrate this, imagine a line with a positive slope. It rises as you move from left to right. A line parallel to it will also rise at the same rate, hence having the same slope. Conversely, a line with a negative slope falls as you move from left to right, and a parallel line will fall at the same rate. This visual understanding can be incredibly helpful in solidifying the concept of parallel lines and their slopes. Remember, the slope is the key! It's the DNA that determines whether lines are parallel to each other. So, with the slope of our target line firmly in hand, let's move on to the next step: using the point-slope form.

Utilizing the Point-Slope Form

Now that we know the slope of our parallel line, we need to figure out its exact equation. This is where the point-slope form comes in handy. The point-slope form is another way to write the equation of a line, and it's particularly useful when you know a point on the line and its slope. The formula for point-slope form is: $y - y_1 = m(x - x_1)$, where m is the slope, and ($x_1$, $y_1$) is the given point that the line passes through.

In our case, we know that the parallel line passes through the point (4, 6). So, we have $x_1 = 4$ and $y_1 = 6$. We also know that the slope m is $- rac3}{2}$, as it's the same as the slope of the line we're parallel to. Now, we simply plug these values into the point-slope form $y - 6 = - rac{3{2}(x - 4)$. This equation represents our line in point-slope form. It tells us everything we need to know about the line: its slope and a point it passes through. However, it's not in the familiar slope-intercept form yet. To get it into slope-intercept form, which is often preferred for its clarity, we need to do a little bit of algebraic manipulation.

The point-slope form is a powerful tool because it allows us to construct the equation of a line directly from its geometric properties – its slope and a point it contains. It bridges the gap between the visual representation of a line on a graph and its algebraic representation as an equation. Think of it as a blueprint for the line. You provide the key ingredients (the slope and a point), and the point-slope form assembles them into a complete equation. This makes it an indispensable tool in various mathematical contexts, not just for finding equations of parallel lines. So, let's move on to the final step of transforming our point-slope equation into the more recognizable slope-intercept form.

Converting to Slope-Intercept Form

We've got our equation in point-slope form: $y - 6 = - rac3}{2}(x - 4)$. Now, let's transform it into slope-intercept form ($y = mx + b$), which will make it even easier to understand and work with. To do this, we need to isolate y on one side of the equation. This involves a couple of algebraic steps. First, we distribute the slope ($- rac{3}{2}$) on the right side of the equation $y - 6 = - rac{32}x + 6$. Notice how we multiplied $- rac{3}{2}$ by both x and -4. It's crucial to distribute correctly to maintain the equality of the equation. Next, we add 6 to both sides of the equation to isolate y $y = - rac{32}x + 6 + 6$. This simplifies to $y = - rac{3{2}x + 12$.

And there you have it! We've successfully converted the equation into slope-intercept form. We can now clearly see that the slope of our line is $- rac{3}{2}$ (which we already knew) and the y-intercept is 12. This means the line crosses the y-axis at the point (0, 12). The slope-intercept form is particularly useful because it provides a direct visual interpretation of the line's key characteristics. The slope tells us the steepness and direction of the line, and the y-intercept tells us where it crosses the vertical axis. This makes it a powerful tool for graphing and analyzing linear equations.

In summary, to find the equation of a line parallel to $y = - rac3}{2}x - 1$ and passing through the point (4, 6), we followed these steps identified the slope of the given line, used the point-slope form to create an equation using the parallel slope and the given point, and then converted the equation to slope-intercept form for clarity. The final equation of our parallel line is $y = - rac{3{2}x + 12$. This equation represents a line that runs parallel to the original line and passes through the specified point. You've nailed it!

Conclusion

Finding the equation of a line parallel to another line might seem daunting at first, but as we've seen, it's a manageable process with the right tools and understanding. The key takeaways here are the concept of parallel lines having the same slope, the usefulness of the point-slope form, and the ability to convert between different forms of linear equations. By mastering these concepts, you'll be well-equipped to tackle similar problems in the future.

Remember, practice makes perfect! The more you work with these equations and concepts, the more comfortable you'll become. So, don't hesitate to try out more examples and challenge yourself. And most importantly, have fun with it! Math can be a fascinating journey of discovery, and each problem you solve is a step forward on that journey. So go forth and conquer those equations, guys!