Is the line with equation x = 4 horizontal or vertical? What is the slope of this line?

Question

phi · Answer

plot two points with x=4
when x=4, y can be anything. so plot (4,0) and (4,1)
draw a line through these points

anonymous · Answer

Vertical.
Pi/2 or 90 degrees

anonymous · Answer

it only says to find the slope, so its anything?

anonymous · Answer

and isnt it horizontal cause its on the x axis

phi · Answer

slope is change in y divided by change in x
change in y for (4,0) and (4,1) is 1-0=1
change in x is 4-4 =0
1/0 is undefined

vertical lines have undefined slope

anonymous · Answer

oh so its 0?

phi · Answer

vertical lines have undefined slope

anonymous · Answer

ok so then  y = -8 is horizonal and is undefined?

phi · Answer

y= -8 means y is -8 and x is anything. so (0,-8) and (1,-8) are on the line
now find change in y divided by change in x

anonymous · Answer

i still dont get it

phi · Answer

Does this make sense
y= -8 means y is -8 and x is anything.

anonymous · Answer

yes

phi · Answer

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