document.write( "Question 94766This question is from textbook Algerbra 2
\n" ); document.write( ": Decide wether the lines ae parallel, perpendicular, or neither\r
\n" ); document.write( "\n" ); document.write( "34. Line 1 contains (4,-4) and (-16, 1)
\n" ); document.write( " Line 2 contains (1, 5)and(5, 21) \n" ); document.write( "

Algebra.Com's Answer #69008 by Edwin McCravy(20060) $\"\"$ $\"About$

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document.write( "Decide wether the lines ae parallel, perpendicular, or neither \r\n" );
document.write( "34. Line 1 contains (4,-4) and (-16, 1)\r\n" );
document.write( "Line 2 contains (1, 5)and(5, 21)\r\n" );
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document.write( "Draw them and see how they look:\r\n" );
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document.write( "They look perpendicular, so let's find their slopes and see\r\n" );
document.write( "if one is the reciprocal of the other with the opposite sign.\r\n" );
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document.write( "Slope formula\r\n" );
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document.write( "     y2 - y1 \r\n" );
document.write( "m = ---------\r\n" );
document.write( "     x2 - x1\r\n" );
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document.write( "For line 1, (x1,y1) = (4,-4) and (x2,y2) = (-16, 1)\r\n" );
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document.write( "      (1) - (-4)       1 + 4       5\r\n" );
document.write( "m = ------------- = --------- =  ----- = \r\n" );
document.write( "     (-16) - (4)     -16 - 4      -20\r\n" );
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document.write( "For line 2, (x1,y1) = (1, 5) and (x2,y2) = (5, 21)\r\n" );
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document.write( "     (21) - (5)       16      \r\n" );
document.write( "m = ------------- = --------- =  or \r\n" );
document.write( "     (5) - (1)         4      \r\n" );
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document.write( "Yes,  and + are reciprocals of each other\r\n" );
document.write( "but with the opposite sign. So they are perpendicular.\r\n" );
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document.write( "Edwin

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