Question 1180629
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 parallel lines 3x - y + 2 = 0 and 3x - y + 7 = 0
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Not the only method, but:


slope of the two given lines, {{{3}}}.   Slope for any line perpendicular to them,  {{{-1/3}}}.  Pick any point on one of the given lines you want.  Find equation of PERPENDICULAR line containing that point.  Find where this intersects the OTHER GIVEN line.  Now, use the distance formula to find distance between these two points.