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## find the slope of the line y = 8 and x = -5 or are they undefined

please show your work so I can know how to do this

Slope of a line between 2 points of a line given by Δy , = difference in vertical coordinates of 2 points
ΔX      difference in the horizontal coordinate of 2 points
X = 5  is a line parallel to Vertical axis:

All points along the line X=5 have the same vertical value , their difference is always f 0 ,
then:

ΔY = 0
ΔX

Y  =8 :   is a line parallel with horizontal axis : all points along it have the same value of X, therefore;
the difference is always 0

Δx  = 0

ΔyΔy    = undefined
Δx     0

Hi Shekinah;
y=8
The slope is defined as change-of-y divided by change-of-x...
(y-y1)/(x-x1)
(8-8)/(x-x1)
0/(x-x1)
x and x1 can be any two points.  The situation is that the sum of zero is in the numerator.  The slope is defined as zero.

x=-5
(y-y1)/(x-x1)
(y-y1)/(-5--5)
(y-y1)/0
Zero is the denominator, also called the divisor.  Nothing can be divided by zero.  This is an undefined slope.

y = 0 is the equation of a line with 0 slope and y intercept 8.

In other words, y = mx + b ⇒ y = (0)x + 8 ⇒ y = 8.

Similarly, x = -5 is a line perpendicular to the y-axis (i.e., infinite slope) and x-intercept -5.  There is no y-intercept.