Question 432324
 Determine whether the lines are parallel, perpendicular, or neither. 

y = 5( 4x + 9) and y = - 1/20x - 4 

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y = 20x+45
slope = 20
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y = (-1/20)x -4
slope = -1/20
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Since the product of the slopes is -1
the lines are parallel.
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Cheers,
Stan H.