Math Problem Statement

Find an equation for the line that passes through the points (5, -1) and (-1, 1).

Solution

The task is to find the equation of a line passing through the points (5,1)(5, -1) and (1,1)(-1, 1).

To find the equation of the line, we can use the point-slope form of the equation of a line:

yy1=m(xx1)y - y_1 = m(x - x_1)

Where:

  • (x1,y1)(x_1, y_1) is one of the points on the line, and
  • mm is the slope of the line, calculated by:

m=y2y1x2x1m = \frac{y_2 - y_1}{x_2 - x_1}

Step 1: Calculate the slope mm

Using the points (x1,y1)=(5,1)(x_1, y_1) = (5, -1) and (x2,y2)=(1,1)(x_2, y_2) = (-1, 1):

m=1(1)15=26=13m = \frac{1 - (-1)}{-1 - 5} = \frac{2}{-6} = -\frac{1}{3}

Step 2: Use the point-slope form

Now, using point (5,1)(5, -1) and the calculated slope m=13m = -\frac{1}{3}, we can substitute into the point-slope form:

y(1)=13(x5)y - (-1) = -\frac{1}{3}(x - 5)

This simplifies to:

y+1=13(x5)y + 1 = -\frac{1}{3}(x - 5)

Now, you can simplify further to get it into slope-intercept form if needed:

y+1=13x+53y + 1 = -\frac{1}{3}x + \frac{5}{3}

y=13x+531y = -\frac{1}{3}x + \frac{5}{3} - 1

y=13x+23y = -\frac{1}{3}x + \frac{2}{3}

So, the equation of the line is:

y=13x+23y = -\frac{1}{3}x + \frac{2}{3}

Would you like more details on this process or have any further questions? Here are some related questions you could explore:

  1. How do you convert the equation from point-slope to slope-intercept form?
  2. What is the significance of the slope in the equation of a line?
  3. How do you graph the equation of a line given two points?
  4. Can you find the equation of the line passing through two other points, say (2,4)(2, 4) and (6,2)(6, -2)?
  5. How would the equation change if the slope was positive instead of negative?

Tip: To always find the slope, remember it’s the change in yy-values divided by the change in xx-values. This is often called "rise over run."

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Linear Equations
Point-Slope Form

Formulas

Point-Slope form: y - y1 = m(x - x1)
Slope formula: m = (y2 - y1) / (x2 - x1)

Theorems

Point-Slope Theorem

Suitable Grade Level

Grades 8-10