SOLUTION: y = 3x y = 3x + 10 i need to find the distance between the parallel lines

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Question 109989: y = 3x
y = 3x + 10
i need to find the distance between the parallel lines

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the distance is the length of a perpendicular line drawn between the parallel lines

perpendicular means the slope will be -1/3 (negative reciprocal of 3)
... 10 is the y-intercept of the upper line, so the perpendicular will match it
... the perpendicular intersects the top line at (0,10)

the intersection with the bottom line is when 3x=(-1/3)x+10 ... or x=3 ... so the intersection is (3,9)

the distance is between the two intersections ... d^2=(3-0)^2+(9-10)^2