document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=574725>Question 574725</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello,<BR>\n" );
document.write( "Pls help me to solve this:<BR>\n" );
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document.write( "Select the pair of equation whose graphs are perpendicular;<BR>\n" );
document.write( "A)2x - 8y = 9 & 12x - 3y = 7<BR>\n" );
document.write( "B)3x + 6y = 8 & y = 2x - 8<BR>\n" );
document.write( "C)y = 2x - 7 & x + y = 3<BR>\n" );
document.write( "D)2y = -3x +5 & 2x + 3y = 4<BR>\n" );
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document.write( "Thanks\r<BR>\n" );
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document.write( "P.S:(This is the 2nd time that I am submitting this problem without receiving any answer) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #369255 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=369255\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Strategy is to find the slope of both equations.  If the slopes are \"negative reciprocal\" the two lines are perpendicular.  That is, the slopes multiplied results in -1.<BR>\n" );
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document.write( "A)2x - 8y = 9 & 12x - 3y = 7<BR>\n" );
document.write( "slope of:<BR>\n" );
document.write( "2x - 8y = 9<BR>\n" );
document.write( "-8y = -2x+9<BR>\n" );
document.write( "8y = 2x-9<BR>\n" );
document.write( "y = (1/4)x-9/8 (slope is 1/4)<BR>\n" );
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document.write( "slope of:<BR>\n" );
document.write( "12x - 3y = 7<BR>\n" );
document.write( "-3y = -12x+7<BR>\n" );
document.write( "3y = 12x-7<BR>\n" );
document.write( "y = 4x-7/3 (slope is 4)<BR>\n" );
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document.write( "4(1/4) = 1 (NO, not perpendicular)<BR>\n" );
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document.write( "B)3x + 6y = 8 & y = 2x - 8<BR>\n" );
document.write( "slope of:<BR>\n" );
document.write( "3x + 6y = 8<BR>\n" );
document.write( "6y = -3x+8<BR>\n" );
document.write( "y = (-1/2)x+8/6 (slope is -1/2)<BR>\n" );
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document.write( "slope of:<BR>\n" );
document.write( "y = 2x - 8  (slope is 2)<BR>\n" );
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document.write( "(-1/2)(2) = -1  (YES, it is perpendicular)\r<BR>\n" );
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document.write( "No need to solve the last two..<BR>\n" );
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document.write( "C)y = 2x - 7 & x + y = 3<BR>\n" );
document.write( "D)2y = -3x +5 & 2x + 3y = 4<BR>\n" );
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