Graph The Following Line Equation: Y = -1/2x + 3

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In the realm of mathematics, understanding how to graph linear equations is a fundamental skill. A linear equation, when graphed, produces a straight line, hence the name. This line visually represents all the possible solutions to the equation. One of the most common forms for a linear equation is the slope-intercept form, which provides a clear and concise way to understand the line's characteristics. In this article, we will delve into the specifics of graphing the linear equation y = -1/2x + 3, providing a step-by-step guide to help you visualize this equation on a coordinate plane. We will cover key concepts such as slope, y-intercept, and how to plot points to accurately draw the line. By the end of this discussion, you will not only be able to graph this particular equation but also gain a solid understanding of how to graph any linear equation in slope-intercept form. Whether you are a student learning the basics of algebra or someone looking to refresh your knowledge, this comprehensive guide will equip you with the necessary tools and techniques to confidently graph linear equations. So, let's embark on this mathematical journey and unravel the intricacies of graphing lines.

Before we begin graphing the equation y = -1/2x + 3, it's crucial to understand the slope-intercept form of a linear equation. This form is written as y = mx + b, where m represents the slope of the line and b represents the y-intercept. The slope, m, indicates the steepness and direction of the line. It is defined as the "rise over run," meaning the change in the y-coordinate divided by the change in the x-coordinate between any two points on the line. A positive slope indicates that the line rises as you move from left to right, while a negative slope indicates that the line falls. The y-intercept, b, is the point where the line crosses the y-axis. It is the value of y when x is equal to zero. In our equation, y = -1/2x + 3, we can clearly identify the slope and y-intercept. The slope, m, is -1/2, which means that for every 2 units you move to the right on the graph, the line goes down 1 unit. The y-intercept, b, is 3, indicating that the line crosses the y-axis at the point (0, 3). Understanding these two key components is essential for accurately graphing the line. By identifying the slope and y-intercept, we can easily plot points and draw the line, making the slope-intercept form a powerful tool for visualizing linear equations. This foundational knowledge will enable us to proceed with graphing our specific equation with confidence and precision.

To effectively graph the line represented by the equation y = -1/2x + 3, the first step is to pinpoint the slope and y-intercept. As we discussed, the equation is already in slope-intercept form, y = mx + b, where m is the slope and b is the y-intercept. By comparing our equation to the general form, we can directly identify these values. The coefficient of x in the equation is -1/2, which means that the slope (m) is -1/2. This negative slope tells us that the line will descend as we move from left to right on the graph. For every 2 units we move horizontally (run), the line will drop 1 unit vertically (rise). This understanding of the slope's direction and steepness is crucial for plotting accurate points on the graph. Next, we identify the y-intercept. The constant term in the equation is 3, which means that the y-intercept (b) is 3. This signifies that the line will intersect the y-axis at the point (0, 3). The y-intercept serves as our starting point when graphing the line. We can plot this point on the coordinate plane and then use the slope to find additional points. With the slope and y-intercept clearly identified, we have the necessary information to begin plotting the graph of the equation. This foundational step ensures that our graph will accurately represent the linear relationship defined by y = -1/2x + 3. In the subsequent sections, we will use these values to plot points and draw the line, solidifying our understanding of graphing linear equations.

Now that we have identified the y-intercept as 3, our next step is to plot this point on the coordinate plane. The y-intercept is the point where the line crosses the y-axis, and it always has an x-coordinate of 0. Therefore, the y-intercept of 3 corresponds to the point (0, 3) on the coordinate plane. To plot this point, we start at the origin (0, 0), which is the intersection of the x-axis and the y-axis. Since the x-coordinate is 0, we do not move left or right along the x-axis. We then move 3 units upward along the y-axis. This brings us to the point (0, 3), which is where we place our first dot on the graph. This dot represents the y-intercept and serves as our anchor point for drawing the line. It is the starting point from which we will use the slope to find other points on the line. Plotting the y-intercept accurately is crucial because it sets the vertical position of the line on the coordinate plane. A mistake in plotting the y-intercept will result in an incorrect graph. Once we have plotted the y-intercept, we can move on to using the slope to find additional points and complete the graph of the line. This step-by-step approach ensures that we construct the graph with precision and clarity. With the y-intercept plotted, we are one step closer to visualizing the linear equation y = -1/2x + 3.

With the y-intercept plotted, we now leverage the slope to find additional points on the line. As we determined earlier, the slope of the line y = -1/2x + 3 is -1/2. The slope represents the “rise over run,” which means for every 2 units we move horizontally (run), the line will drop 1 unit vertically (rise, in this case, a fall because it's negative). Starting from our y-intercept point (0, 3), we can use the slope to find our next point. We move 2 units to the right along the x-axis (run of 2), and then 1 unit down along the y-axis (rise of -1). This brings us to the point (2, 2). We can plot this point on the coordinate plane. To find another point, we can repeat this process. Starting from (2, 2), we move another 2 units to the right (run of 2) and 1 unit down (rise of -1). This lands us at the point (4, 1). We plot this point as well. By using the slope, we have generated two additional points on the line. These points, along with the y-intercept, give us a clear path to draw the line. The more points we plot, the more accurate our line will be. It's important to note that we could also move in the opposite direction by using the negative run. For example, starting from the y-intercept (0, 3), we could move 2 units to the left (run of -2) and 1 unit up (rise of 1), which would give us the point (-2, 4). This point also lies on the line. Using the slope to find multiple points ensures that our line is accurately positioned and represents the equation y = -1/2x + 3 correctly.

Having plotted at least two points, including the y-intercept, we are now ready to draw the line that represents the equation y = -1/2x + 3. To draw the line, we need a straightedge, such as a ruler or any object with a straight edge. Place the straightedge so that it aligns with the points we have plotted. In our case, we have at least the y-intercept (0, 3) and the point (2, 2), and potentially (4, 1) or (-2, 4) if we used the slope to find additional points. Once the straightedge is aligned with the points, carefully draw a line that extends through the points and spans the entire coordinate plane. The line should pass through all the plotted points, indicating that these points are solutions to the equation y = -1/2x + 3. Extend the line beyond the plotted points to show that the line continues infinitely in both directions. Add arrows to the ends of the line to further emphasize its infinite extent. This is a standard convention in graphing linear equations. A well-drawn line should be straight and clear, accurately representing the relationship between x and y as defined by the equation. If the line does not pass through all the plotted points, it indicates a possible error in plotting the points or in drawing the line. In such cases, it's essential to review the previous steps and correct any mistakes. The final drawn line is a visual representation of all the solutions to the equation y = -1/2x + 3. Every point on the line corresponds to a pair of x and y values that satisfy the equation. This visual representation is a powerful tool for understanding and analyzing linear equations. With the line drawn, we have successfully graphed the equation and can now use the graph to answer questions about the relationship between x and y.

After drawing the line, it is crucial to verify the graph to ensure its accuracy. There are several methods we can use to confirm that the line correctly represents the equation y = -1/2x + 3. One method is to choose a point on the line and substitute its coordinates into the equation. If the equation holds true, then the point is indeed on the line. For example, we can choose the point (2, 2), which we plotted earlier. Substituting x = 2 and y = 2 into the equation, we get: 2 = -1/2(2) + 3. Simplifying the equation, we have 2 = -1 + 3, which is 2 = 2. Since the equation is true, the point (2, 2) is correctly placed on the line. We can repeat this process with another point, such as (4, 1). Substituting x = 4 and y = 1 into the equation, we get: 1 = -1/2(4) + 3. Simplifying, we have 1 = -2 + 3, which is 1 = 1. This confirms that the point (4, 1) is also correctly plotted. Another method to verify the graph is to check the slope and y-intercept directly from the drawn line. We can visually inspect the line to see if it crosses the y-axis at the point (0, 3), which is our y-intercept. We can also check the slope by choosing two points on the line and calculating the rise over run. If the calculated slope matches the slope in the equation (-1/2), then our graph is likely correct. Furthermore, we can use graphing software or calculators to plot the equation and compare the result with our hand-drawn graph. This provides an additional layer of verification. By employing these verification methods, we can confidently say that our graph accurately represents the equation y = -1/2x + 3. This step is essential for ensuring the correctness of our work and for building a strong understanding of graphing linear equations.

In conclusion, graphing the line represented by the equation y = -1/2x + 3 involves a systematic process that builds upon fundamental concepts of linear equations. We began by understanding the slope-intercept form (y = mx + b), which allows us to easily identify the slope and y-intercept of the line. For our equation, we determined that the slope is -1/2 and the y-intercept is 3. We then plotted the y-intercept at the point (0, 3) on the coordinate plane. Using the slope, we found additional points on the line, such as (2, 2) and (4, 1), by applying the “rise over run” concept. With these points plotted, we carefully drew a straight line through them, extending it across the coordinate plane and adding arrows to indicate its infinite extent. Finally, we verified the accuracy of our graph by substituting points into the equation and checking if the equation held true. We also visually inspected the graph to ensure that the y-intercept and slope matched our initial calculations. This step-by-step approach ensures that we have accurately represented the equation y = -1/2x + 3 graphically. The ability to graph linear equations is a crucial skill in mathematics and has applications in various fields, including physics, engineering, and economics. By mastering this skill, you can visually represent and analyze linear relationships, making it easier to solve problems and gain insights into real-world situations. With practice and a solid understanding of the underlying concepts, you can confidently graph any linear equation and unlock the power of visual representation in mathematics.