Math - slope of vertical line?

Question

why is the slope of a vertical line -1 and no 0?

thanks

Answer 1

The slope of a vertical line is infinite.

Answer 2

The slope of a vertical line is technically not defined.
The slope of any line is the rise per unit run.
Thus the slope of a horizontal line would be zero, because if you run one unit length along it, it rises zero height.
A line that goes goes down at an angle of 45 degrees will be -1, because it goes down one unit for one unit length run.
A vertical line keeps going up or down without running horizontal. Therefore even without any horizontal run the line will go vertically to either plus infinity or minus infinity.
The slope of a vertical line can, therefore be plus infinity or minus infinity.
Now strictly speaking,
Since the slope in rise per unit run, we get the slope of a line by doing just that. Divide the rise by run. A vertical line has zero run. And a vertical line has zero horizontal run.
Division by zero is not permitted.
Therefore slope of a vertical is really not defined.

Answer 3

you are mistaken
the slope of the vertical line is not defined,
since you would have to divide by 0,

the slope of a horizontal line is 0
and the line with slope -1 is a line that goes through the origin (0,0) and
(-1,1)

Answer 4

perpendicular lines have negative reciprocal slopes. since horizontal lines have zero as their slope, then the slope of a vertical line is -1/0. which is undefined.

Answer 5

further explaination
the formula of the slope of the line
is

(ysub2-ysub1)/(xsub2-xsub1)

in which

this is

from

two points in a line
called
(xsub1,ysub1),
(xsub2,ysub2)

when the line is vertical

the point of x is equal

xsub1=xsub2

so

change in y/ 0 is undefine



furtheremore the more peakness of the line
the more high value of slope
wherein the near in vertical position means aproaching to the big values or approaching to infinity of slope so it is undefine value when vertical line.


.

Answer 6

slope of a line is passing through (x1,y1) and (x2,y2)
is

(y1-y2)/(x1-x2)

for a vertical line x1 = x2 so denominator is zero so slope is infinite and not 0 or = -1 . slope of a line is also tan t where t is the angle with x axis
slope is -1 for a line passing through (0,0) and (1, -1)

Answer 7

sophisticated problem look on at yahoo and bing it may help

Answer 8

i think you are wrong,as a vertical line is always undefined....what about 0,its for a horizontal line and -1 is for perpendicular lines.

Answer 9

I am not sure.

A slope of an line is tan(angle it makes with the X-axis).
So its tan(90)= Infiniti.

tan(45)=1 so tan(-45)=(-1)=tan(360-45)

Peace out.