document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=970160>Question 970160</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An isosceles triangles's base is 15 cm and the other two sides are 21cm. Find its area </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #592811 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=592811\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The isosceles triangle can have the base split into two halves, each 7.5 cm long.\r<BR>\n" );
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document.write( "Now the altitude is one of the legs of a right triangle with the other leg 7.5 and hypotenuse 21\r<BR>\n" );
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document.write( "56.25 (1/2 of base squared) + x^2 = 441 (21^2)   Pythagorean Theorem.<BR>\n" );
document.write( "Subtract 56.25 from each side.<BR>\n" );
document.write( "x^2= 384.75\r<BR>\n" );
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document.write( "x=19.61 cm  positive root only.\r<BR>\n" );
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document.write( "That is the altitude.\r<BR>\n" );
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document.write( "The area is (1/2) bh<BR>\n" );
document.write( "base is 15 cm, altitude 19.61 cm\r<BR>\n" );
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document.write( "0.5 * 15 *19.61=147.075 cm^2 </SPAN>\n" );
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