document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=84019>Question 84019</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me with this--Find the area of a parallelogram ABCD, if m Ang A = 60 degrees, AB=10, and AD = 4sqrt(3).  I am lost! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #60487 by </B><A HREF=/tutors/aboutme.mpl?userid=vertciel><B>vertciel(183)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vertciel><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=60487\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> *I would assume that this problem involves the use of trigonometry. I was not sure so I am offering a solution without trigonometry. If it actually involves trig, I can offer another solution.\r<BR>\n" );
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document.write( "• Draw a tidy diagram of this problem. Label what you know.\r<BR>\n" );
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document.write( "• Denote the intersection of angles (perpendicular bisector in parallelograms) any letter you want. I'll call it O.\r<BR>\n" );
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document.write( "• A parallelogram's area = Base x Height. However, height is not given here. \r<BR>\n" );
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document.write( "• We can also find area by another way. Twice the area of the triangles formed by the diagonals = the area of the parallelogram. \r<BR>\n" );
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document.write( "So, the area of the parallelogram = Area of triangles ACD + ABD or Area of triangles BDC + BAC (either set works).\r<BR>\n" );
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document.write( "I'll stick with ACD + ABD:, so all you need to do is calculate the area of either ACD or ABD. I'll pick ACD. \r<BR>\n" );
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document.write( "You know AD is the base, but you don't know the height. However, O is perpendicular so triangle COD is a right angle triangle. You have CD = 10 and AD = 4sqrt(3). Use the Pythagoras Theorem to find out OC, which is rounded to 9.38.\r<BR>\n" );
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document.write( "So now you know triangle ACD's area = 4sqrt(3) x 9.38 \r<BR>\n" );
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document.write( "                                    = 64.987 \r<BR>\n" );
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document.write( "So double that, and you get 129.974 sq. units, which is area of the entire parallelogram.\r<BR>\n" );
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