Question 173186
 Determine whether the graphs of the equations are parallel lines, perpendicular lines, or neither. 
3x - 8y = -18
32x + 12y = -18
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Find the slope, m, of both by putting them into slope-intercept form
3x - 8y = -18
8y = 3x + 18
y = (3/8)x + 9/4
m1 = 3/8
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32x + 12y = -18
12y = -32x - 18
6y = -16x - 9
y = (-8/3)x - 3/2
m2 = -8/3
That's the negative inverse of m1, so they're perpendicular