document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=650170>Question 650170</A>: <I><SPAN STYLE=\"word-break: break-all;\"> use slopes to show that the quadrilateral whose vertices are (1.-1), (4,1),(2,2), and (5,4) is a parallelogram </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #407209 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=407209\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> first, a slope for (1.-1), (4,1)\r<BR>\n" );
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document.write( " <TR><TD  ALIGN=MIDDLE>Solved by <A  rel=nofollow HREF=http://wiki.algebra.com/index.php/Tutoring_-_pluggable_solvers>pluggable</A> solver: <A  rel=nofollow HREF=slope.solver>Finding the slope</A></TD></TR>\n" );
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document.write( "  Slope of the line through the points (1, -1) and (4, 1)<BR>\n" );
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document.write( "  Answer: Slope is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+2%2F3 ALIGN=MIDDLE  ALT=\"m+=+2%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "next, a slope for (2,2), and (5,4)\r<BR>\n" );
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document.write( " <TR><TD  ALIGN=MIDDLE>Solved by <A  rel=nofollow HREF=http://wiki.algebra.com/index.php/Tutoring_-_pluggable_solvers>pluggable</A> solver: <A  rel=nofollow HREF=slope.solver>Finding the slope</A></TD></TR>\n" );
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document.write( "  Slope of the line through the points (2, 2) and (5, 4)<BR>\n" );
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document.write( "  Answer: Slope is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+2%2F3 ALIGN=MIDDLE  ALT=\"m+=+2%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "lines have same slope; s0, they are parallel\r<BR>\n" );
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document.write( "next, a slope for (1.-1), and (2,2)\r<BR>\n" );
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document.write( " <TR><TD  ALIGN=MIDDLE>Solved by <A  rel=nofollow HREF=http://wiki.algebra.com/index.php/Tutoring_-_pluggable_solvers>pluggable</A> solver: <A  rel=nofollow HREF=slope.solver>Finding the slope</A></TD></TR>\n" );
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document.write( "  Slope of the line through the points (1, -1) and (2, 2)<BR>\n" );
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document.write( "  Answer: Slope is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+3 ALIGN=MIDDLE  ALT=\"m+=+3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "and, a slope for (1.-1), and (2,2)\r<BR>\n" );
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document.write( " <TR><TD  ALIGN=MIDDLE>Solved by <A  rel=nofollow HREF=http://wiki.algebra.com/index.php/Tutoring_-_pluggable_solvers>pluggable</A> solver: <A  rel=nofollow HREF=slope.solver>Finding the slope</A></TD></TR>\n" );
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document.write( "  Slope of the line through the points (4, 1) and (5, 4)<BR>\n" );
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document.write( "  Answer: Slope is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+3 ALIGN=MIDDLE  ALT=\"m+=+3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "lines have same slope; s0, they are parallel\r<BR>\n" );
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document.write( "if both pairs of sides are parallel, then you can conclude that those four points define the <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=vertex ALIGN=MIDDLE  ALT=\"vertex\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+points ALIGN=MIDDLE  ALT=\"+points\"   DISABLED_style= \"max-width:90%; height:auto;\" > of a <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=parallelogram ALIGN=MIDDLE  ALT=\"parallelogram\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "as you can see, their intersection is a <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=parallelogram ALIGN=MIDDLE  ALT=\"parallelogram\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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