Question 417899
are the graphs of the two lines 
2x-3y=6
y = (2/3)x -2
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2x+3y=9
y = (-2/3)x+3
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parallel: No because the slopes are not the same.
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perpendicular: No because (2/3)(-2/3) is not -1
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neither: Yes
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Cheers,
Stan H.