document.write( "Question 621707: Determine whether each pair of equations represents perpendicular lines.
\n" ); document.write( "y=5-3x, 3x-y=8\r
\n" ); document.write( "\n" ); document.write( "Thank you,
\n" ); document.write( "Janice
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Algebra.Com's Answer #390888 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
If you have a line that looks like
\n" ); document.write( "\"+y+=+m%2Ax+%2B+b%5B1%5D+\", then a line perpendicular to it
\n" ); document.write( "looks like \"+y+=+%28-1%2Fm+%29%2Ax+%2B+b%5B2%5D+\" where \"+m+\" is slope
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\n" ); document.write( "Your lines are
\n" ); document.write( "(1) \"+y+=+5+-+3x+\"
\n" ); document.write( "(2) \"+3x+-+y=+8+\"
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\n" ); document.write( "(1) \"+y+=+-3x+%2B+5+\"
\n" ); document.write( "and
\n" ); document.write( "(2) \"+-y+=+-3x+%2B+8+\"
\n" ); document.write( "Multiply both sides by \"-1\"
\n" ); document.write( "(2) \"+y+=+3x+-+8+\"
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\n" ); document.write( "Now compare the slopes. They are
\n" ); document.write( "\"+m%5B1%5D+=+-3+\"
\n" ); document.write( "and
\n" ); document.write( "\"+m%5B2%5D+=+3+\"
\n" ); document.write( "They can't be perpendicular because
\n" ); document.write( "\"+m%5B1%5D+=+-m%5B2%5D+\" and to be perpendicular,
\n" ); document.write( "\"+m%5B1%5D+=+-1%2Fm%5B2%5D+\"
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