document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=319797>Question 319797</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is the area of a triangle with lengths of sides of 20, 31 and 43? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #229046 by </B><A HREF=/tutors/aboutme.mpl?userid=nyc_function><B>nyc_function(2741)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nyc_function><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=nyc_function><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=229046\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Use Heron's Formula to find your area. The triangle has 3 different sides and so this tells me that it is a scalene triangle.\r<BR>\n" );
document.write( "\n" );
document.write( "Let sqrt = square root\r<BR>\n" );
document.write( "\n" );
document.write( "Let A = area of scalene triangle\r<BR>\n" );
document.write( "\n" );
document.write( "Let a + b + c = sides of triangle\r<BR>\n" );
document.write( "\n" );
document.write( "Let s = half of the triangle's perimeter\r<BR>\n" );
document.write( "\n" );
document.write( "s = (a + b + c)/2\r<BR>\n" );
document.write( "\n" );
document.write( "The formula is A = sqrt{s(s - a)(s - b)(s - c)}\r<BR>\n" );
document.write( "\n" );
document.write( "The given sides: \r<BR>\n" );
document.write( "\n" );
document.write( "a = 20<BR>\n" );
document.write( "b = 31<BR>\n" );
document.write( "c = 43\r<BR>\n" );
document.write( "\n" );
document.write( "We need to find the value of letter s as step one.  Just plug and chug.\r<BR>\n" );
document.write( "\n" );
document.write( "s = (20 + 31 + 43)/2\r<BR>\n" );
document.write( "\n" );
document.write( "s = 94/2\r<BR>\n" );
document.write( "\n" );
document.write( "s = 47\r<BR>\n" );
document.write( "\n" );
document.write( "We can now use the formula given above.\r<BR>\n" );
document.write( "\n" );
document.write( "A = sqrt{s(s - a)(s - b)(s - c)}\r<BR>\n" );
document.write( "\n" );
document.write( "We also plug and chug.\r<BR>\n" );
document.write( "\n" );
document.write( "A = sqrt{47(47 - 20)(47 - 31)(47 - 43)}\r<BR>\n" );
document.write( "\n" );
document.write( "A = sqrt{47(27)(16)(4)}\r<BR>\n" );
document.write( "\n" );
document.write( "A = sqrt{47(1728)}\r<BR>\n" );
document.write( "\n" );
document.write( "A = sqrt{81216}\r<BR>\n" );
document.write( "\n" );
document.write( "A = 284.9842101, Which can be rounded to the nearest unit (or ones place) to make the answer 285.\r<BR>\n" );
document.write( "\n" );
document.write( "To learn more about Heron's Formula, copy and paste the link below.\r<BR>\n" );
document.write( "\n" );
document.write( "http://www.mathsisfun.com/geometry/herons-formula.html\r<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );