Find the slope of the line through points (5, 1) and (-2, 3) and through points (-1, -1) and (-1, 4).

Posted on

Hi, Eli,

The slope of a line has a formula:

slope = m = (`y_(2)` - `y_(1)` )/(`x_(2)` - `x_(1)` )

The 2 and 1 stand for which point the number comes from.  For instance, we could have:

Point 1 = (5,1)

Point 2 = (-2,3)

They can be switched, it wouldn't make a difference.

Then, plugging in the numbers:

m = (3 - 1)/(-2 - 5) = 2/-7 = -2/7

(If we had the numbers switched, then we would have had (-2)/7, neagtive on top, which would still be the same as -2/7)

For the second pair of points, following the same procedure:

m = (4 - -1)/(-1 - -1) = 5/0 = undefined.

So, I have heard teachers use different terms for this slope, undefined or no slope mostly.  But, this isn't zero slope.

Good luck, Eli.  I hope this helps.

Till Then,

Steve

Posted on

To find the slope you have to use the
`(y2-y1)/(x2-x1)`

(5,1)(-2,3)

y2= 3     y1= 1

x2=-2     x1= 5

`(3-1)/(-2-5)` = `(2)/(-7)` is the Slope

(-1,-1)(-1,4)

y2= 4    y1=-1

x2=-1    x1=-1

`(4-(-1))/(-1-(-1))` = `(5)/(0)` is the slope