Math Problem Statement

Graph the line that passes through the points (0, -8) and (5, -5) and determine the equation of the line.

Solution

We are given two points (0,8)(0, -8) and (5,5)(5, -5) and need to determine the equation of the line passing through them.

Step 1: Find the slope (mm)

The slope formula is:

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

Substitute (x1,y1)=(0,8)(x_1, y_1) = (0, -8) and (x2,y2)=(5,5)(x_2, y_2) = (5, -5):

m=5(8)50=5+85=35m = \frac{-5 - (-8)}{5 - 0} = \frac{-5 + 8}{5} = \frac{3}{5}

So, the slope m=35m = \frac{3}{5}.

Step 2: Use the point-slope form

The point-slope form of the equation of a line is:

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

Substituting m=35m = \frac{3}{5} and the point (0,8)(0, -8):

y(8)=35(x0)y - (-8) = \frac{3}{5}(x - 0)

Simplifying:

y+8=35xy + 8 = \frac{3}{5}x

Now, subtract 8 from both sides:

y=35x8y = \frac{3}{5}x - 8

Thus, the equation of the line is:

y=35x8y = \frac{3}{5}x - 8

Step 3: Graph the line

  • The line passes through the points (0,8)(0, -8) and (5,5)(5, -5).
  • The slope m=35m = \frac{3}{5} means that for every 5 units to the right, the line goes up 3 units.
  • The y-intercept is 8-8, meaning the line crosses the y-axis at (0,8)(0, -8).

Would you like a more detailed explanation or graphing assistance?

Here are some related questions for practice:

  1. How do you find the slope if given two points?
  2. What is the point-slope form of a linear equation?
  3. How can you identify the y-intercept from an equation?
  4. How does the slope affect the direction of a line on a graph?
  5. Can you find the equation of a line perpendicular to this one?

Tip: Always check that your line passes through both points by substituting them back into the equation.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Coordinate Geometry
Linear Equations

Formulas

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

Theorems

-

Suitable Grade Level

Grade 8-10