document.write( "Question 154238: A. Find the equation of the line passing through the points (3, -5) and ( 1, -2).\r
\n" ); document.write( "\n" ); document.write( "B. Find the equation of the line perpendicular to the line you found above and passing throught the point ( -1, - 2)
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Algebra.Com's Answer #113546 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
(a) The formula is:
\n" ); document.write( "
\n" ); document.write( "where
\n" ); document.write( "(3, -5) is (\"x%5B1%5D\",\"y%5B1%5D\")
\n" ); document.write( "(1, -2) is (\"x%5B2%5D\",\"y%5B2%5D\")
\n" ); document.write( "Actually, you could interchange (3, -5) and (1, -2) and you'd
\n" ); document.write( "still get the right answer
\n" ); document.write( "-------------------------------
\n" ); document.write( "\"%28y+-+%28-5%29%29+%2F+%28x+-+3%29+=+%28-2+-+%28-5%29%29+%2F+%281+-+3%29\"
\n" ); document.write( "\"%28y+%2B+5%29+%2F+%28x+-+3%29+=+3+%2F+%28-2%29\"
\n" ); document.write( "Multiply both sides by \"%28x+-+3%29%2A%28-2%29\"
\n" ); document.write( "\"%28-2%29%2A%28y+%2B+5%29+=+3%2A%28x+-+3%29\"
\n" ); document.write( "\"-2y+-+10+=+3x+-+9\"
\n" ); document.write( "\"-2y+=+3x+%2B+1\"
\n" ); document.write( "\"y+=+-%283%2F2%29x+-+1%2F2\" answer
\n" ); document.write( "check answer:
\n" ); document.write( "Does the line pass through (3, -5) and (1, -2)?
\n" ); document.write( "\"-5+=+-%283%2F2%29%2A3+-+1%2F2\"
\n" ); document.write( "\"-5+=+-%289%2F2%29+-+1%2F2\"
\n" ); document.write( "\"-5+=+-5\"
\n" ); document.write( "OK
\n" ); document.write( "\"-2+=+-%283%2F2%29%2A1+-+1%2F2\"
\n" ); document.write( "\"-2+=+-2\"
\n" ); document.write( "OK
\n" ); document.write( "-------
\n" ); document.write( "(b)The slope of the line perpendicular to this
\n" ); document.write( "line must have a slope \"m%5B2%5D+=+-%281%2Fm%5B1%5D%29\"
\n" ); document.write( "where \"m%5B1%5D+=+-%283%2F2%29\"
\n" ); document.write( "\"m%5B2%5D+=+2%2F3\"
\n" ); document.write( "It passes through (-1 , -2)
\n" ); document.write( "I can use the point-slope formula for this
\n" ); document.write( "\"m+=+%28y+-+y%5B1%5D%29+%2F+%28x+-+x%5B1%5D%29\"
\n" ); document.write( "\"2%2F3+=+%28y+-+%28-2%29%29+%2F+%28x+-+%28-1%29%29\"
\n" ); document.write( "\"2%2F3+=+%28y+%2B+2%29+%2F+%28x+%2B+1%29\"
\n" ); document.write( "Multiply both sides by \"3%2A%28x+%2B+1%29\"
\n" ); document.write( "\"2%2A%28x+%2B+1%29+=+3%2A%28y+%2B+2%29\"
\n" ); document.write( "\"2x+%2B+2+=+3y+%2B+6\"
\n" ); document.write( "\"3y+=+2x+-+4\"
\n" ); document.write( "\"y+=+%282%2F3%29x+-+4%2F3\"
\n" ); document.write( "---------------------
\n" ); document.write( "Does it pass through (-1, -2)?
\n" ); document.write( "\"-2+=+%282%2F3%29%2A%28-1%29+-+4%2F3\"
\n" ); document.write( "\"-2+=+-%282%2F3%29+-+4%2F3\"
\n" ); document.write( "\"-2+=+-2\"
\n" ); document.write( "OK
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