Equation Of Line QR Passing Through Q(0, 1) And R(2, 7)

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In the realm of coordinate geometry, lines stand as fundamental entities, and their representation through equations is a cornerstone concept. The equation of a line encapsulates its essence, defining its slope, intercept, and the relationship between its x and y coordinates. When given two points on a line, our task is to decipher this equation, and we can do this by employing a potent arsenal of techniques. This article delves into the process of determining the equation of a line, specifically line QR, which gracefully traverses through the points Q(0, 1) and R(2, 7). By meticulously calculating the slope and harnessing the point-slope form, we will unveil the equation that reigns over this line. In the world of mathematics, the elegance of finding a line's equation lies in its practical applications. Whether we are mapping trajectories, designing structures, or modeling trends, understanding how lines behave is paramount. To embark on this mathematical voyage, we will first need to calculate the slope of the line using the given coordinates. Slope is the heart of any linear equation, dictating the line's steepness and direction. It is the ratio of vertical change (the "rise") to horizontal change (the "run") between two points on the line. With the slope in hand, we can then choose a point and use the point-slope form to construct the equation. This form is a powerful tool, allowing us to express the equation of a line using just a single point and the slope. It bridges the gap between abstract coordinates and the tangible line they represent. As we progress, we will not just mechanically apply formulas, but also cultivate a deeper understanding of why these methods work. The goal is to transform mathematical problems into visual stories, where lines dance across the coordinate plane, each equation telling a unique tale. So, prepare to sharpen your pencils and engage your minds as we embark on this journey to discover the equation of line QR, a beacon of understanding in the vast landscape of mathematics. Let us begin by exploring the significance of slope in defining a line and how to calculate it from the coordinates of two points.

Calculating the Slope: The Foundation of the Line

To begin our quest, we must first determine the slope of line QR. The slope, often denoted by the letter 'm', quantifies the steepness and direction of a line. It essentially tells us how much the y-coordinate changes for every unit change in the x-coordinate. The formula to calculate the slope (m) given two points, (x1, y1) and (x2, y2), is a simple yet powerful one: m = (y2 - y1) / (x2 - x1). This formula embodies the essence of linear progression, revealing how the line inclines or declines as we move along the x-axis. In our specific case, we have the points Q(0, 1) and R(2, 7). Let's assign Q as (x1, y1) and R as (x2, y2). Plugging these values into our slope formula, we get m = (7 - 1) / (2 - 0). This simplifies to m = 6 / 2, which further reduces to m = 3. Thus, we have successfully calculated the slope of line QR, and it stands at 3. This positive slope indicates that the line rises as we move from left to right on the coordinate plane. For every one unit we move along the x-axis, the line ascends three units along the y-axis. Now, armed with the slope, we have a crucial piece of the puzzle. The slope is not just a number; it is the heartbeat of the line, dictating its inclination and behavior. It is the constant rate of change that defines the linear relationship between x and y. With the slope firmly in our grasp, we can now move on to the next step: employing the point-slope form to craft the equation of the line. The point-slope form is a versatile tool that allows us to express the equation of a line using just a single point and the slope. It is a bridge that connects the abstract world of coordinates and slopes to the tangible representation of a line on the graph. As we delve into the point-slope form, we will witness how this fundamental concept transforms the slope and a single point into a powerful equation that governs the line's trajectory. Understanding the slope is essential, but it's only half the story. The point-slope form allows us to weave the slope and a specific point into a comprehensive equation that captures the line's identity. So, let's now explore the magic of the point-slope form and how it unlocks the equation of line QR.

Point-Slope Form: Constructing the Equation

Now that we have the slope (m = 3), we can utilize the point-slope form to determine the equation of line QR. The point-slope form is a powerful tool, expressed as y - y1 = m(x - x1), where (x1, y1) is a point on the line and m is the slope. This form is invaluable because it directly incorporates the slope and a known point to construct the line's equation. We have two points at our disposal, Q(0, 1) and R(2, 7). We can choose either point to plug into the point-slope form. Let's opt for point Q(0, 1) as our (x1, y1). Substituting the values into the point-slope form, we get y - 1 = 3(x - 0). Simplifying this equation, we have y - 1 = 3x. This equation is already in a form that closely resembles one of the answer choices, but let's explore further to ensure we fully understand the concept. The point-slope form is more than just a formula; it's a way of expressing the linear relationship between x and y in terms of a specific point and the rate of change. It highlights how the y-coordinate changes relative to the x-coordinate as we move along the line, anchored at the chosen point. This form is particularly useful because it allows us to quickly write the equation of a line given minimal information – just a single point and the slope. It bypasses the need to first calculate the y-intercept, which is often required when using the slope-intercept form (y = mx + b). By choosing point Q(0, 1), we've effectively anchored our equation at that location. The term '3(x - 0)' tells us how the y-coordinate changes as we move away from x = 0, guided by the slope of 3. If we had chosen point R(2, 7) instead, we would have arrived at an equivalent equation, albeit in a slightly different form. The point-slope form gracefully handles different starting points, ultimately leading to the same line equation. To solidify our understanding, let's consider what the equation y - 1 = 3x truly represents. It paints a picture of a line that passes through the point (0, 1) and rises three units for every one unit we move to the right. It's a dynamic description of the line's behavior, not just a static equation. Now, with the equation in hand, we can confidently compare it to the given answer choices and pinpoint the correct representation of line QR. This final step solidifies our understanding and demonstrates the power of the point-slope form in solving linear equation problems.

Identifying the Correct Equation

Having derived the equation y - 1 = 3x using the point-slope form, our next task is to compare this equation with the provided answer choices and identify the one that accurately represents line QR. The answer choices are:

A. y - 1 = 6x B. y - 1 = 3x C. y - 7 = 2x - 6 D. y - 7 = x - 2

By direct comparison, we can see that answer choice B, y - 1 = 3x, perfectly matches the equation we obtained. Therefore, option B is the correct representation of line QR. However, to ensure our solution is comprehensive, let's also examine why the other options are incorrect. Option A, y - 1 = 6x, suggests a line with a slope of 6, which is twice the slope we calculated for line QR. This line would be steeper than the actual line QR. Options C and D are presented in a slightly different form, but we can still analyze them. Option C, y - 7 = 2x - 6, can be rewritten as y = 2x + 1. This equation represents a line with a slope of 2, which is different from our calculated slope of 3. Furthermore, if we substitute the coordinates of point Q(0, 1) into this equation, we get 1 = 2(0) + 1, which is true. However, if we substitute the coordinates of point R(2, 7), we get 7 = 2(2) + 1, which simplifies to 7 = 5, a clear contradiction. Therefore, option C does not represent line QR. Similarly, option D, y - 7 = x - 2, can be rewritten as y = x + 5. This equation has a slope of 1, again different from our calculated slope of 3. Substituting the coordinates of point Q(0, 1) into this equation, we get 1 = 0 + 5, which is false. Thus, option D is also incorrect. Our thorough analysis confirms that only option B, y - 1 = 3x, accurately represents the equation of line QR. This process of elimination not only reinforces the correctness of our chosen answer but also deepens our understanding of linear equations and their graphical representations. By meticulously comparing our derived equation with each answer choice, we demonstrate a comprehensive approach to problem-solving, ensuring that our solution is both accurate and well-supported.

Conclusion: The Equation Unveiled

In this comprehensive exploration, we embarked on a journey to determine the equation of line QR, which gracefully traverses through the points Q(0, 1) and R(2, 7). We began by laying the foundation, understanding the significance of slope in defining a line's steepness and direction. We then meticulously calculated the slope using the coordinates of the given points, arriving at a value of m = 3. This slope became the cornerstone of our quest, guiding us toward the line's true identity. Armed with the slope, we ventured into the realm of the point-slope form, a powerful tool that allows us to construct the equation of a line using a single point and the slope. We chose point Q(0, 1) and skillfully applied the point-slope form, unveiling the equation y - 1 = 3x. This equation encapsulated the essence of line QR, defining its trajectory across the coordinate plane. With the equation in hand, we engaged in a careful comparison with the provided answer choices, meticulously analyzing each option. Through this process, we confidently identified option B, y - 1 = 3x, as the correct representation of line QR. Our journey did not stop at simply finding the answer; we delved deeper, examining why the other options were incorrect. This thorough analysis not only reinforced the correctness of our solution but also deepened our understanding of linear equations and their graphical interpretations. We saw how different slopes and y-intercepts create distinct lines, each with its unique characteristics. This exploration underscores the elegance and power of coordinate geometry. By combining fundamental concepts like slope and point-slope form, we can unravel the equations that govern lines, unlocking their secrets and revealing their mathematical harmony. The ability to determine the equation of a line given two points is a fundamental skill in mathematics, with applications spanning diverse fields, from physics and engineering to economics and computer science. As we conclude this journey, we carry with us not just the equation of line QR, but also a deeper appreciation for the beauty and utility of linear equations. The line QR, once an abstract concept, now stands vividly before us, defined by its equation, a testament to the power of mathematical reasoning. This quest has illuminated the path to understanding linear relationships, empowering us to tackle future mathematical challenges with confidence and insight.