document.write( "Question 57486: Are the following lines parallel, perpendicular, or neither?
\n" ); document.write( " L1 with equation x – 4y = 12
\n" ); document.write( " L2 with equation 4x + y = 4
\n" ); document.write( " \n" ); document.write( "
Algebra.Com's Answer #39246 by funmath(2933)\"\" \"About 
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Are the following lines parallel, perpendicular, or neither?
\n" ); document.write( " L1 with equation x – 4y = 12
\n" ); document.write( " L2 with equation 4x + y = 4
\n" ); document.write( "Putting equations is slope intercept form \"highlight%28y=mx%2Bb%29\", m=slope, (0,b)=y-intercept, makes it easy to see their slopes. Parallel lines have = slopes, perpendicular lines have slopes that are negative reciprocals (opposite signs and upside down), if they aren't either of those, it's neither.
\n" ); document.write( "L1) x-4y=12
\n" ); document.write( "-x+x-4y=-x+12
\n" ); document.write( "-4y=-x+12
\n" ); document.write( "-4y/-4=-x/-4+12/-4
\n" ); document.write( "y=(1/4)x-3 The slope of L1, m=1/4
\n" ); document.write( "L2) 4x+y=4
\n" ); document.write( "-4x+4x+y=-4x+4
\n" ); document.write( "y=-4x+4 The slope of L2 is m=-4/1
\n" ); document.write( "The slopes are negative reciprocals of each other, therefore the lines are perpendicular. \n" ); document.write( "
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