SOLUTION: Hi, Find the distance from point (2, -3) to the line {{{3x-y=4}}} Thanks :D

Algebra ->  Vectors -> SOLUTION: Hi, Find the distance from point (2, -3) to the line {{{3x-y=4}}} Thanks :D      Log On


   



Question 450557: Hi,
Find the distance from point (2, -3) to the line 3x-y=4
Thanks :D

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find the distance from point (2, -3) to the line 3x-y=4
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The distance from a point to a line can be an infinite # of values.
To find the shortest distance:
The slope of 3x-y = 4 is 3.
Lines perpendicular will have a slope that's the negative inverse, m = -1/3.
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Find the eqn of the line with a slope of -1/3 that passes thru (2,-3)
Use y = mx + b
-3 = (-1/3)*2 + b
b = -7/3
--> y = -x/3 - 7/3 is the eqn of the line thru (2,-3) perpendicular to the other line.
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Find the intersection of the 2 lines
3x - y = 4
Sub for y
3x - (-x/3 - 7/3) = 4
10x/3 + 7/3 = 4
10x + 7 = 12
x = 1/2
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y = -5/2
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Find the distance from (2,-3) to (1/2,-5/2)
d+=+sqrt%28diffy%5E2+%2B+diffx%5E2%29+=+sqrt%281%2F4+%2B+9%2F4%29
d = sqrt(10)/2
d =~ 1.5811