Question 457208
( 7, 8) and ( 7, -8) 
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slope = (-8-8)/(7-7) = -16/0
which is "not defined".
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Notice that both points have x=7.
Plot those two points and you will get
a vertical line passing thru all the
points where x=7
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Equation of the line: x = 7
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Cheers,
Stan H.
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