document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1165477>Question 1165477</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The side of a regular pentagon is 25 cm. If the radius of its inscribed circle is 15 cm, find the area of the pentagon.<BR>\n" );
document.write( "a. 937.5 cm2 b. 784.6 cm2<BR>\n" );
document.write( "c. 825.75 cm2 d. 857.65 cm2 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #790019 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=790019\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The circle hits the sides and itself has area of πr^2=225 π or 706.86 cm^2\r<BR>\n" );
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document.write( "Draw this and note the 10 triangles that may be made. We know that because the central angle of each of those is 36 degrees and 360/36=10.<BR>\n" );
document.write( "They are 36 degrees, because the internal angles of the pentagon are each 108 degrees {(n-2)/n}*180, and the line from the center to the vertex of each angle bisects it, so that is where 54 degrees comes from.\r<BR>\n" );
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document.write( "The area of each triangle is (1/2) bh with base 12.5 (half the side's length)  and height 15 (the radius), so each triangle has area 93.75 cm^2. There are 10 of them, and the total area is 937.5 cm^2 <BR>\n" );
document.write( "A </SPAN>\n" );
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