# slope of a line

• December 7th 2006, 06:21 PM
Schatzle06
slope of a line
A line is represented by the equation x = 6. What is the slope of the line?

a. 0 b. 5/6

c. 6 d. undefined

This is for extra points, that I really need in my algebra II class =).
• December 7th 2006, 06:22 PM
AfterShock
Quote:

Originally Posted by Schatzle06
A line is represented by the equation x = 6. What is the slope of the line?

a. 0 b. 5/6

c. 6 d. undefined

This is for extra points, that I really need in my algebra II class =).

d, undefined. It is a vertical line.

Note: a horizontal line, y = ... has slope 0.
• December 7th 2006, 06:23 PM
Jacobpm64
Well, the line x = 6 looks like a vertical line ( up and down ) ... going through the point (6, 0) on the x-axis.

Vertical lines have an undefined slope.

So,
D. Undefined.
• December 8th 2006, 04:46 AM
topsquark
Quote:

Originally Posted by Schatzle06
A line is represented by the equation x = 6. What is the slope of the line?

a. 0 b. 5/6

c. 6 d. undefined

This is for extra points, that I really need in my algebra II class =).

Go back to your basic definition:
$m = \frac{y_2 - y_1}{x_2 - x_1}$

We can get two points on this line: say (6, 1) and (6, 2).

$m = \frac{2 - 1}{6 - 6} = \frac{1}{0}$

Since we can't divide by 0, this slope is undefined.

Comment:
You have now posted several extra credit questions. I have noticed that many of the solutions depend directly on basic definitions. If the definitions are giving you problems I would strongly recommend you review these with your teacher to make sure you understand them. Otherwise, as I think Aftershock mentioned, none of this will help you.

-Dan