document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=979881>Question 979881</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find an equation for the line with the given properties. Express the answer using the general form of the equation of a line.\r<BR>\n" );
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document.write( "Perpendicular to the line -4x + 5y = -23; containing the point (-3, 7)\r<BR>\n" );
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document.write( "I almost sure the answer is -5x + 4y = -13 but I dont know for sure<BR>\n" );
document.write( "Thank you for your time </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #601120 by </B><A HREF=/tutors/aboutme.mpl?userid=Cromlix><B>Cromlix(4381)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Cromlix><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=Cromlix><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=601120\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> hi there,<BR>\n" );
document.write( "Sort -4x + 5y = -23<BR>\n" );
document.write( "into y = mx + c form<BR>\n" );
document.write( "5y = 4x - 23<BR>\n" );
document.write( "Divide through by 5<BR>\n" );
document.write( "y = 4/5 - 23/5<BR>\n" );
document.write( "Gradient = 4/5.<BR>\n" );
document.write( "Lines that are perpendicular have<BR>\n" );
document.write( "gradients that multiply together<BR>\n" );
document.write( "to give -1<BR>\n" );
document.write( "m1 x m2 = -1<BR>\n" );
document.write( "Therefore the new line has a <BR>\n" );
document.write( "gradient of -5/4 (4/5 x -5/4 = -1)<BR>\n" );
document.write( "Using the coords -3,7 and the line<BR>\n" );
document.write( "equation:<BR>\n" );
document.write( "y - b = m(x - a)<BR>\n" );
document.write( "y - 7 = -5/4(x - (-3))<BR>\n" );
document.write( "y - 7 = -5/4(x + 3)<BR>\n" );
document.write( "y - 7 = -5/4x -15/4<BR>\n" );
document.write( "y = -5/4x - 15/4 + 28/4 (7)<BR>\n" );
document.write( "y = -5/4x + 13/4<BR>\n" );
document.write( "Multiply throughout by 4<BR>\n" );
document.write( "4y = -5x + 13<BR>\n" );
document.write( "5x + 4y = 13<BR>\n" );
document.write( "Hope this helps:-) </SPAN>\n" );
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