document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=174231>Question 174231</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Which statement is true of the given lines?\r<BR>\n" );
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document.write( "Line a: -2x+y=4   Line b: 2x+5y=2   Line c: x+2y=4\r<BR>\n" );
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document.write( "a) Lines a and b are parallel.<BR>\n" );
document.write( "b) Lines a and c are parallel.<BR>\n" );
document.write( "c) Lines a and b are perpendicular.<BR>\n" );
document.write( "d) Lines a and c are perpendicular. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #129159 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=129159\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Rewriting each of the given equation into the \"point-slope\" form of<BR>\n" );
document.write( "y = mx + b<BR>\n" );
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document.write( "Line a: -2x+y=4<BR>\n" );
document.write( "y = 2x+4 <BR>\n" );
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document.write( "Line b: 2x+5y=2 <BR>\n" );
document.write( "5y = -2x+2<BR>\n" );
document.write( "y = (-2/5)x + 2/5<BR>\n" );
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document.write( "Line c: x+2y=4 <BR>\n" );
document.write( "2y = -x + 4<BR>\n" );
document.write( "y = (-1/2)x + 2<BR>\n" );
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document.write( "Since NO two lines have the same slope -- no lines are parallel.<BR>\n" );
document.write( "Now, if two lines are \"negative reciprocals\" then they are perpendicular.<BR>\n" );
document.write( "Slope of line a: 2<BR>\n" );
document.write( "Slope of line c: -1/2<BR>\n" );
document.write( "They are \"negative reciprocals\" -- <BR>\n" );
document.write( "that is, if you multiply the two slopes you'll get -1<BR>\n" );
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document.write( "Answer would be -- d) Lines a and c are perpendicular. </SPAN>\n" );
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