SOLUTION: 1.7x-4y=4 x-4y=3 tell whether the line for each pair of equations are parallel,prependicular,or nither

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Question 249108: 1.7x-4y=4
x-4y=3
tell whether the line for each pair of equations are parallel,prependicular,or nither

Answer by College Student(505) About Me  (Show Source):
You can put this solution on YOUR website!
Is the "1." meant to signify this is your first problem? Or is your problem actually 1.7x? I'm going to presume my first thought to be correct.

Parallel, perpendicular, or neither?
7x-4y=4 and x-4y=3

Facts:
1. In order for two lines be parallel, they must share the same slope.
2. In order for two lines be perpendicular, the product of their slopes must equal -1.
3. The easiest form of identifying the slope is by expressing the equation in this form: y=mx%2Bb where m = slope.

7x-4y=4
-4y=-7x%2B4
y=%28-7x%2F-4%29%2B%284%2F-4%29
y=%287%2F4%29x-1 <--- slope is 7%2F4

x-4y=3
-4y=-x%2B3
y=%281%2F4%29x-%283%2F4%29 <--- slope is 1%2F4

Analize the results:
1. 7%2F4 is not equal to 1%2F4, therefore these lines are not parallel.
2. %287%2F4%29%281%2F4%29=7%2F16, therefore these lines are not perpendicular either.
3. The answer to this problem is: neither.

Just for kicks, here's how their graphs look like:
y=%287%2F4%29x-1 is represented in red
y=%281%2F4%29x-%283%2F4%29 is represented in green