document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1205848>Question 1205848</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Given ABCD is a trapezoid with BC parallel to AD. If AB = AD = 4, angle A = 60 degrees, and angle C = 45 degrees, determine the value of length DC. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #842914 by </B><A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><B>math_tutor2020(3817)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><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=842914\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "Refer to the diagram that tutor Edwin has posted.\r<BR>\n" );
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document.write( "Triangle ABE is a 30-60-90 triangle, so AB = 4 leads to AE = 2.<BR>\n" );
document.write( "The short leg (AE) is half as long as the hypotenuse (AB) for 30-60-90 triangles.<BR>\n" );
document.write( "The long leg of 30-60-90 triangles is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%283%29 ALIGN=MIDDLE  ALT=\"sqrt%283%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > times that of the short leg.<BR>\n" );
document.write( "Therefore we can state <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=EB+=+AE%2Asqrt%283%29+=+2%2Asqrt%283%29 ALIGN=MIDDLE  ALT=\"EB+=+AE%2Asqrt%283%29+=+2%2Asqrt%283%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Triangle DFC is a 45-45-90 triangle.<BR>\n" );
document.write( "The hypotenuse DC is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%282%29 ALIGN=MIDDLE  ALT=\"sqrt%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > times that of the leg length <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=DC+=+DF%2Asqrt%282%29 ALIGN=MIDDLE  ALT=\"DC+=+DF%2Asqrt%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=DC+=+2%2Asqrt%283%29%2Asqrt%282%29 ALIGN=MIDDLE  ALT=\"DC+=+2%2Asqrt%283%29%2Asqrt%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=DC+=+2%2Asqrt%283%2A2%29 ALIGN=MIDDLE  ALT=\"DC+=+2%2Asqrt%283%2A2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=DC+=+2%2Asqrt%286%29 ALIGN=MIDDLE  ALT=\"DC+=+2%2Asqrt%286%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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