Question 839741
if the slope is undefined, it's because you have a vertical line.


the rule is:


if the equation is y = c, you have a horizontal line.
if the equation is x = c, you have a vertical line.


c represents any constant.


your point is (-1,7) and your slope is undefined.


you have a vertical line.


a vertical line has an infinite number of values for y that can occur at the specified value of x.


your vertical line will be at x = -1.


y = 7 is a point on that line.
there are an infinite number of other points that are on that line and they all have their x-coordinate as -1.
some example:
(-1,7)
(-1,9)
(-1,15,000,000,000)
(-1,-15,000,000,000)


a graph of your equation will look something like this:
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