Question 416430
Decide whether the pair of lines is parallel, perpendicular, or neither
5x+3y=9
3x-5y=8 
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Slope-intercept form:
y = (-5/3)x + 3
y = (3/5)x - (8/3)
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Since (-5/3)(3/5) = -1
the lines are perpendicular.
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Cheers,
Stan H.
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