Question 672996
slope is {{{(y1-y2)/(x1-x2) = (-7-9)/(3-3) = -16/0}}}
slope is undefined, as 0 cannot be in the denominator
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The line is a vertical line at 3 on the x axis.  The line has a rise, or change in y axis, but no run, or change in x axis.
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Equation for the line is x=3
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