document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=318522>Question 318522</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the area of an equilateral triangle that has a perimeter of 21 inches.  Round the answer to one decimal place. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #227977 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=227977\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=drawing%28300%2C300%2C-10%2C10%2C-10%2C10%2Cline%28-3%2C0%2C3%2C0%29%2Cline%28-3%2C0%2C0%2C4.24%29%2Cline%280%2C0%2C0%2C4.24%29%2Clocate%28-3%2C3%2Cs%29%2Clocate%282.5%2C3%2Cs%29%2Clocate%280.5%2C2%2Ch%29%2C+locate%280%2C-0.5%2Cs%29%2Cline%28-0.5%2C0%2C-0.5%2C0.5%29%2Cline%28-0.5%2C0.5%2C0%2C0.5%29%2Cline%283%2C0%2C0%2C4.24%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ".<BR>\n" );
document.write( ".<BR>\n" );
document.write( ".\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=%281%2F2%29bh ALIGN=MIDDLE  ALT=\"A=%281%2F2%29bh\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ".<BR>\n" );
document.write( ".<BR>\n" );
document.write( ".<BR>\n" );
document.write( "Find h using the Pythagorean theorem.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h%5E2=s%5E2-%28s%2F2%29%5E2 ALIGN=MIDDLE  ALT=\"h%5E2=s%5E2-%28s%2F2%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h%5E2=s%5E2%2F2 ALIGN=MIDDLE  ALT=\"h%5E2=s%5E2%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h=%28sqrt%282%29%2F2%29%2As ALIGN=MIDDLE  ALT=\"h=%28sqrt%282%29%2F2%29%2As\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=%281%2F2%29s%28sqrt%282%29%2F2%29s ALIGN=MIDDLE  ALT=\"A=%281%2F2%29s%28sqrt%282%29%2F2%29s\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=%28sqrt%282%29%2F4%29s%5E2 ALIGN=MIDDLE  ALT=\"A=%28sqrt%282%29%2F4%29s%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ".<BR>\n" );
document.write( ".<BR>\n" );
document.write( ".<BR>\n" );
document.write( "Find <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s ALIGN=MIDDLE  ALT=\"s\"   DISABLED_style= \"max-width:90%; height:auto;\" > using the perimeter.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P=3s=21 ALIGN=MIDDLE  ALT=\"P=3s=21\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s=7 ALIGN=MIDDLE  ALT=\"s=7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substitute,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=%2849%2Asqrt%282%29%29%2F4 ALIGN=MIDDLE  ALT=\"A=%2849%2Asqrt%282%29%29%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > or approximately,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=17.324 ALIGN=MIDDLE  ALT=\"A=17.324\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "The area is 17.3 sq. inches. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );