document.write( "Question 16749: what is the distance between\r
\n" ); document.write( "\n" ); document.write( "y=1/2x,y=1/2x+5
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Algebra.Com's Answer #8465 by rapaljer(4671)\"\" \"About 
You can put this solution on YOUR website!
y=1/2x is the graph of a straight line with y intercept 0 and slope m=1/2
\n" ); document.write( "y=1/2x + 5 is the graph of a straight line with y intercept 5 and slope m = 1/2.\r
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\n" ); document.write( "\n" ); document.write( "The second line is exactly the same as the first line, except that it is moved \"up\" 5 units. \r
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\n" ); document.write( "\n" ); document.write( "If you rewrite these equations in standard form there is a formula for the distance from a point on a given line to another given line. Let's rewrite these equations in standard form as
\n" ); document.write( "y = 1/2x, which is 2y= x or x-2y=0
\n" ); document.write( "y=1/2x + 5, which is 2y = x + 10 or x-2y +10= 0\r
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\n" ); document.write( "\n" ); document.write( "The formula (if I remember correctly from about 15 years ago!!)is :
\n" ); document.write( "Distance from a point to a given line: \"+d+=+%28abs%28Ax%2BBy+%2B+C%29%29%2F%28sqrt%28A%5E2+%2B+B%5E2%29%29+\", where Ax+By+C = 0 is the equation of the line, and (x,y) is a given point (in this case, any point you choose to select from the other line--let's say the point (0,0) on the first line, since this is an easy point to see and to calculate).\r
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\n" ); document.write( "\n" ); document.write( "So, let (0,0) be a point on the first line, and find the perpendicular distance from (0,0) to the line x-2y+10 = 0.\r
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\n" ); document.write( "\n" ); document.write( "In the formula, A= 1, B=-2, C= 10, x=0, and y=0:\r
\n" ); document.write( "\n" ); document.write( "\"+d+=+%28abs%28Ax%2BBy+%2B+C%29%29%2F%28sqrt%28A%5E2+%2B+B%5E2%29%29+\"
\n" ); document.write( "\"+d+=+%28abs%281%2A0%2B%28-2%29%2A0+%2B+10%29%29%2F%28sqrt%281%5E2+%2B+%28-2%29%5E2%29%29+\"
\n" ); document.write( "\"d=+10%2Fsqrt%285%29+=+%2810%2Asqrt%285%29%29%2F%28sqrt%285%29%2Asqrt%285%29%29+\"
\n" ); document.write( "\"d+=+%2810%2Asqrt%285%29%29%2F5\"
\n" ); document.write( "\"d+=+2%2Asqrt%285%29\"\r
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\n" ); document.write( "\n" ); document.write( "Someone may have an easier way, but this is what I recall from a LONG time ago!\r
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\n" ); document.write( "\n" ); document.write( "R^2 at SCC
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