document.write( "Question 431948: Determine whether the line through P1 and P2 is parallel, perpendicular, or neither parallel nor perpendicular to the line through Q1 and Q2.\r
\n" ); document.write( "\n" ); document.write( "1). P1(4,-5)P2(6,-9);Q1(5,-4)Q2(1,4)\r
\n" ); document.write( "\n" ); document.write( "2). P1(5,1)P2(3,-2);Q1(0,-2)Q2(3,-4)\r
\n" ); document.write( "\n" ); document.write( "3). P1(1,-1)P2(3,-2);Q1(-4,1)Q2(2,-5) \n" ); document.write( "
Algebra.Com's Answer #299630 by ewatrrr(24785)\"\" \"About 
You can put this solution on YOUR website!

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document.write( "Hi
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document.write( "Using the point-slope formula, \"m+=%28y%5B2%5D+-+y%5B1%5D%29%2F%28x%5B2%5D+-+x%5B1%5D%29\"
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document.write( "P1(4,-5)
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document.write( "P2(6,-9)  m = 4/-2 = -2
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document.write( "Q1(5,-4)
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document.write( "Q2(1, 4)  m = -8/4 = -2
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document.write( "line through P1 and P2 is parallel to the line through Q1 and Q2.\r
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document.write( "P1(5, 1)
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document.write( "P2(3,-2) m = 3/2
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document.write( "Q1(0,-2)
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document.write( "Q2(3,-4) m = 2/-3 = -2/3
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document.write( "line through P1 and P2 is perpendicular to the line through Q1 and Q2.\r
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document.write( "P1(1,-1)
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document.write( "P2(3,-2) m = 1/-2 = -1/2
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document.write( "Q1(-4,1)
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document.write( "Q2(2,-5) m = 6/-6 = -1
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document.write( "the line through P1 and P2 is neither parallel nor perpendicular 
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document.write( "to the line through Q1 and Q2. \n" );
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