document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=727274>Question 727274</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The vertices of a quadrilateral are (-1, -1), (1,7), (6,5 ), and (3, -1). What is the area? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #445035 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=445035\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The vertices of a quadrilateral are (-1, -1), (1,7), (6,5 ), and (3, -1). What is the area?<BR>\n" );
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document.write( "The vertices of a quadrilateral are A(-1,-1), B(1,7), C(6,5), and D(3,-1). What is the area?<BR>\n" );
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document.write( " A. B. C. D. A<BR>\n" );
document.write( "-1 +1 +6 +3 -1<BR>\n" );
document.write( "-1 +7 +5 -1 -1<BR>\n" );
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document.write( "Add the diagonal products starting at the upper left = -7 + 5 - 6 - 3 = -11<BR>\n" );
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document.write( "Add the diagonal products starting at the lower left = -1 + 42 + 15 + 1 = 57<BR>\n" );
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document.write( "Area = 1/2 the difference = 1/2 * 68<BR>\n" );
document.write( "= 34 sq units\r<BR>\n" );
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