Slope-Intercept Form Equation Find With Slope 6/7 And Y-Intercept (0 -5)

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In the realm of mathematics, understanding linear equations is a fundamental concept. One of the most common and intuitive ways to represent a linear equation is through the slope-intercept form. This form provides a clear understanding of the line's characteristics, specifically its slope and y-intercept. In this article, we will delve deep into the slope-intercept form, exploring its components, how to derive it, and its applications. We will focus on the specific problem of finding the slope-intercept equation given a slope of 67\frac{6}{7} and a y-intercept of (0,βˆ’5)(0, -5).

What is Slope-Intercept Form?

The slope-intercept form of a linear equation is expressed as:

y=mx+by = mx + b

Where:

  • yy represents the dependent variable (typically plotted on the vertical axis).
  • xx represents the independent variable (typically plotted on the horizontal axis).
  • mm represents the slope of the line.
  • bb represents the y-intercept of the line.

Understanding the Components

The slope (mm) is a crucial parameter that defines the steepness and direction of the line. It is calculated as the ratio of the change in yy (rise) to the change in xx (run) between any two points on the line. A positive slope indicates that the line rises from left to right, while a negative slope indicates that the line falls from left to right. A slope of zero represents a horizontal line.

The y-intercept (bb) is the point where the line intersects the y-axis. This is the point where the xx-coordinate is zero. The y-intercept provides a fixed point on the line, which, along with the slope, uniquely defines the line.

Finding the Slope-Intercept Equation

To determine the slope-intercept equation of a line, we need two pieces of information: the slope (mm) and the y-intercept (bb). Once we have these values, we can directly substitute them into the slope-intercept form equation, y=mx+by = mx + b.

Given Slope and Y-Intercept

In many cases, the slope and y-intercept are provided directly. This makes the process of finding the equation straightforward. Let's consider the problem presented: find the slope-intercept equation for the line with a slope of 67\frac{6}{7} and a y-intercept of (0,βˆ’5)(0, -5).

Here, we are given:

  • Slope (mm) = 67\frac{6}{7}
  • Y-intercept (bb) = -5 (since the y-intercept is the y-coordinate of the point where the line crosses the y-axis)

Now, we simply substitute these values into the slope-intercept form:

y=mx+by = mx + b

y=67x+(βˆ’5)y = \frac{6}{7}x + (-5)

Simplifying, we get:

y=67xβˆ’5y = \frac{6}{7}x - 5

Therefore, the slope-intercept equation of the line with a slope of 67\frac{6}{7} and a y-intercept of (0,βˆ’5)(0, -5) is y=67xβˆ’5y = \frac{6}{7}x - 5.

Deriving Slope-Intercept Form from Two Points

If, instead of the slope and y-intercept, we are given two points on the line, we can still determine the slope-intercept equation. The process involves two steps:

  1. Calculate the slope (mm) using the two points.
  2. Use the slope and one of the points to find the y-intercept (bb).

Step 1: Calculate the Slope

The slope (mm) can be calculated using the formula:

m=y2βˆ’y1x2βˆ’x1m = \frac{y_2 - y_1}{x_2 - x_1}

Where (x1,y1)(x_1, y_1) and (x2,y2)(x_2, y_2) are the coordinates of the two given points.

Step 2: Find the Y-Intercept

Once we have the slope (mm), we can use the slope-intercept form (y=mx+by = mx + b) and one of the given points to solve for the y-intercept (bb). Substitute the coordinates of the point (xx and yy) and the calculated slope (mm) into the equation and solve for bb.

Deriving Slope-Intercept Form from Standard Form

Another common form of a linear equation is the standard form, represented as:

Ax+By=CAx + By = C

Where AA, BB, and CC are constants.

To convert a standard form equation to slope-intercept form, we need to isolate yy on one side of the equation. This involves algebraic manipulation to rearrange the equation into the form y=mx+by = mx + b.

Applications of Slope-Intercept Form

The slope-intercept form is not just a mathematical concept; it has numerous practical applications in various fields:

  • Graphing Linear Equations: The slope-intercept form makes it easy to graph a linear equation. We can start by plotting the y-intercept and then use the slope to find other points on the line.
  • Modeling Real-World Scenarios: Linear equations are often used to model real-world situations, such as the relationship between time and distance, cost and quantity, or temperature and altitude. The slope-intercept form allows us to easily interpret the rate of change (slope) and the initial value (y-intercept) in these scenarios.
  • Predicting Future Values: By understanding the slope and y-intercept, we can make predictions about future values based on the linear relationship. For example, we can predict the cost of producing a certain number of items or the distance traveled after a certain amount of time.
  • Comparing Linear Relationships: The slope-intercept form provides a convenient way to compare different linear relationships. By comparing their slopes and y-intercepts, we can understand how they differ in terms of rate of change and initial values.

Common Mistakes to Avoid

When working with the slope-intercept form, there are a few common mistakes to be aware of:

  • Incorrectly Identifying the Slope and Y-Intercept: Make sure to correctly identify the slope (mm) and y-intercept (bb) from the equation or given information. The slope is the coefficient of xx, and the y-intercept is the constant term.
  • Mixing Up Slope and Y-Intercept: Avoid confusing the slope and y-intercept. The slope represents the rate of change, while the y-intercept represents the initial value.
  • Incorrectly Calculating the Slope: When calculating the slope from two points, ensure that you subtract the y-coordinates and x-coordinates in the correct order.
  • Not Simplifying the Equation: Always simplify the equation to its simplest form after substituting the values of slope and y-intercept.

Conclusion

The slope-intercept form is a powerful tool for understanding and working with linear equations. By grasping the concepts of slope and y-intercept, we can easily represent linear relationships, graph lines, and solve real-world problems. Whether you are given the slope and y-intercept directly, two points on the line, or the equation in standard form, you can always derive the slope-intercept form through the methods discussed in this article. Remember to pay attention to the details, avoid common mistakes, and practice applying these concepts to solidify your understanding.

By mastering the slope-intercept form, you gain a valuable skill that will serve you well in various mathematical and real-world applications. So, embrace the power of y=mx+by = mx + b and unlock the world of linear equations!