Calculating the Slope between Two Points

Oct 13, 2025 by wbrum.org 118 views

Introduction

In mathematics, the slope of a line is a measure of how steep it is. It is calculated by finding the ratio of the vertical change (rise) to the horizontal change (run) between two points on the line. In this article, we will explore how to calculate the slope of a line between two given points.

What is the Slope of a Line?

The slope of a line is a measure of its steepness. It is calculated by finding the ratio of the vertical change (rise) to the horizontal change (run) between two points on the line. The slope is usually denoted by the letter 'm' and is calculated using the following formula:

m = (y2 - y1) / (x2 - x1)

where (x1, y1) and (x2, y2) are the coordinates of the two points on the line.

Calculating the Slope between Two Points

To calculate the slope between two points, we need to find the vertical change (rise) and the horizontal change (run) between the two points. The vertical change is the difference in the y-coordinates of the two points, while the horizontal change is the difference in the x-coordinates of the two points.

Let's consider the two points given in the problem: (-3, 4) and (1, 7). To calculate the slope between these two points, we need to find the vertical change and the horizontal change.

Vertical Change (Rise)

The vertical change (rise) is the difference in the y-coordinates of the two points. In this case, the y-coordinate of the first point is 4, and the y-coordinate of the second point is 7. Therefore, the vertical change (rise) is:

rise = y2 - y1 = 7 - 4 = 3

Horizontal Change (Run)

The horizontal change (run) is the difference in the x-coordinates of the two points. In this case, the x-coordinate of the first point is -3, and the x-coordinate of the second point is 1. Therefore, the horizontal change (run) is:

run = x2 - x1 = 1 - (-3) = 1 + 3 = 4

Calculating the Slope

Now that we have found the vertical change (rise) and the horizontal change (run), we can calculate the slope between the two points using the formula:

m = (y2 - y1) / (x2 - x1)

Substituting the values we found earlier, we get:

m = (7 - 4) / (1 - (-3)) m = 3 / 4 m = 0.75

Conclusion

In this article, we calculated the slope of a line between two given points. We found the vertical change (rise) and the horizontal change (run) between the two points and used these values to calculate the slope. The slope of the line between the points (-3, 4) and (1, 7) is 3/4.

Answer

The correct answer is C) $\frac{3}{4}$ .

Additional Examples

Here are a few more examples of calculating the slope between two points:

Example 1: Find the slope of the line between the points (2, 5) and (4, 8).
- Vertical change (rise) = 8 - 5 = 3
- Horizontal change (run) = 4 - 2 = 2
- Slope = (8 - 5) / (4 - 2) = 3 / 2 = 1.5
Example 2: Find the slope of the line between the points (-2, 3) and (1, 6).
- Vertical change (rise) = 6 - 3 = 3
- Horizontal change (run) = 1 - (-2) = 1 + 2 = 3
- Slope = (6 - 3) / (1 - (-2)) = 3 / 3 = 1

Tips and Tricks

Here are a few tips and tricks to help you calculate the slope between two points:

Make sure to find the vertical change (rise) and the horizontal change (run) between the two points.
Use the formula m = (y2 - y1) / (x2 - x1) to calculate the slope.
Simplify the fraction if possible.
Check your answer by plugging it back into the formula.

Conclusion

Q: What is the slope of a line?

A: The slope of a line is a measure of how steep it is. It is calculated by finding the ratio of the vertical change (rise) to the horizontal change (run) between two points on the line.

Q: How do I calculate the slope of a line between two points?

A: To calculate the slope of a line between two points, you need to find the vertical change (rise) and the horizontal change (run) between the two points. The vertical change is the difference in the y-coordinates of the two points, while the horizontal change is the difference in the x-coordinates of the two points. Once you have found the vertical change and the horizontal change, you can use the formula m = (y2 - y1) / (x2 - x1) to calculate the slope.

Q: What is the formula for calculating the slope of a line?

A: The formula for calculating the slope of a line is:

m = (y2 - y1) / (x2 - x1)

where (x1, y1) and (x2, y2) are the coordinates of the two points on the line.

Q: How do I simplify the fraction if the slope is not a whole number?

A: If the slope is not a whole number, you can simplify the fraction by dividing both the numerator and the denominator by their greatest common divisor (GCD). For example, if the slope is 3/4, you can simplify it by dividing both 3 and 4 by their GCD, which is 1. This will give you a simplified fraction of 3/4.

Q: What if the horizontal change is zero?

A: If the horizontal change is zero, it means that the two points are the same point. In this case, the slope is undefined, because you cannot divide by zero.

Q: What if the vertical change is zero?

A: If the vertical change is zero, it means that the two points have the same y-coordinate. In this case, the slope is zero, because the ratio of the vertical change to the horizontal change is zero.

Q: Can I use the slope formula to find the equation of a line?

A: Yes, you can use the slope formula to find the equation of a line. Once you have found the slope, you can use the point-slope form of a linear equation to write the equation of the line.

Q: What is the point-slope form of a linear equation?

A: The point-slope form of a linear equation is:

y - y1 = m(x - x1)

where (x1, y1) is a point on the line and m is the slope.

Q: How do I use the point-slope form to write the equation of a line?

A: To use the point-slope form to write the equation of a line, you need to substitute the values of the point and the slope into the formula. For example, if the point is (2, 3) and the slope is 2, you can substitute these values into the formula to get:

y - 3 = 2(x - 2)

Simplifying this equation will give you the equation of the line in slope-intercept form.

Conclusion

In conclusion, calculating the slope of a line between two points is a simple process that involves finding the vertical change (rise) and the horizontal change (run) between the two points and using these values to calculate the slope. With practice and patience, you will become proficient in calculating the slope between two points and using the point-slope form to write the equation of a line.