SOLUTION: please help me understand how to determine if these pairs of lines are perpendicular parallel or neither: 1.y=-4x-4 2. 8x-2y=-2 3.y=4x+8

Algebra ->  Functions -> SOLUTION: please help me understand how to determine if these pairs of lines are perpendicular parallel or neither: 1.y=-4x-4 2. 8x-2y=-2 3.y=4x+8      Log On


   



Question 988090: please help me understand how to determine if these pairs of lines are perpendicular parallel or neither:
1.y=-4x-4
2. 8x-2y=-2
3.y=4x+8

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
Put them all into the form of y=mx+b and compare m.
first is y=-4x-4
second is -2y=-8x-2; divide by -2; y=4x+1
third is y=4x+8
;
Same slopes, different intercepts, parallel.
Different slopes, which when multiplied together are not -1: neither. If multiplication of slopes is -1, then the lines are perpendicular. That is all you have to do.
The second and third have the same slope, so they are parallel. The first has a slope of -4, but since -4*4=-16 and not -1, they intersect and are not perpendicular.
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