Find a slope of a line parallel to 3x minus y equals 1

3x - y = 1

First you have to change this into slope intercept form (y = mx + b).

3x - y = 1
-y = -3x + 1
y = 3x - 1

m = 3
(m is the slope)

So the line parallel to this line will also have a slope of 3.
If they waned the perpendicular line though, it would be the negative reciprocal (-1/3).

The answer is 3.

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