document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=135170>Question 135170</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do I find the equation of a line parallel/perpendicular without a point that it goes through?\r<BR>\n" );
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document.write( "example: y=3x+9 (I don't have a point that it goes through)\r<BR>\n" );
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document.write( "do i just plug in zero for x and solve, then plug zero for y and solve? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #99006 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=99006\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> All you know in this case is the slope of a parallel or perpendicular <BR>\n" );
document.write( "line. If the equation is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+3x+%2B+9 ALIGN=MIDDLE  ALT=\"y+=+3x+%2B+9\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then a parallel line<BR>\n" );
document.write( "will have slope = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3 ALIGN=MIDDLE  ALT=\"3\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "A perpendicular line will have slope = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-%281%2F3%29 ALIGN=MIDDLE  ALT=\"-%281%2F3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >. You can write general<BR>\n" );
document.write( "equations in which the y-intercept is unknown like this:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+3x+%2B+b ALIGN=MIDDLE  ALT=\"y+=+3x+%2B+b\"   DISABLED_style= \"max-width:90%; height:auto;\" > for a parallel line<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+-%281%2F3%29x+%2B+b ALIGN=MIDDLE  ALT=\"y+=+-%281%2F3%29x+%2B+b\"   DISABLED_style= \"max-width:90%; height:auto;\" > for a perpendicular line<BR>\n" );
document.write( "In the parallel case, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b ALIGN=MIDDLE  ALT=\"b\"   DISABLED_style= \"max-width:90%; height:auto;\" > shouldn't be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9 ALIGN=MIDDLE  ALT=\"9\"   DISABLED_style= \"max-width:90%; height:auto;\" >, since that would<BR>\n" );
document.write( "make it the same line as the original. </SPAN>\n" );
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