SOLUTION: Determine which two equations represent parallel lines: (a)y=-9x+4 (b)y=9x+4 (c)y=1/9x+4 (d)y=-9+5

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Question 82568: Determine which two equations represent parallel lines:
(a)y=-9x+4
(b)y=9x+4
(c)y=1/9x+4
(d)y=-9+5
Answer by tutorcecilia(2152) About Me  (Show Source):
You can put this solution on YOUR website!
Lines that are parallel have the same slope. In the y=mx+b formula, the "m" is the slope. So look at each equation and find matching slopes:
(a)and (d) have matching slopes, so these two lines are parallel.