document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=150589>Question 150589</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the altitude of an isosceles trapezoid is 20cm. if the lower base is 10cm longer than the upper base the area of the trapezoid is 220sq. cm, find the lengths of the bases. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #110835 by </B><A HREF=/tutors/aboutme.mpl?userid=jojo14344><B>jojo14344(1513)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jojo14344><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=110835\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Area of a trapezoid is similar to a triangle, the only difference it has 2 bases. If a triangle is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F2%29%28h%29%28b%29 ALIGN=MIDDLE  ALT=\"%281%2F2%29%28h%29%28b%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, we need to add another base to calculate for the area of trapezoid -----> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F2%29h%28a%2Bb%29 ALIGN=MIDDLE  ALT=\"%281%2F2%29h%28a%2Bb%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ".<BR>\n" );
document.write( "In the problem, let \"a\"=upper base=\"x\", \"b\"=lower base=\"x+10cm\", and<BR>\n" );
document.write( "altitude=h=20cm<BR>\n" );
document.write( "Substituting in our eqn with given, A=220 sqcm},<BR>\n" );
document.write( "220 =(1/2)(20)(x+x+10) = (1/2)(20)(2x+10)<BR>\n" );
document.write( "cross multiply,<BR>\n" );
document.write( "440=40x+200<BR>\n" );
document.write( "440-200=40x<BR>\n" );
document.write( "240=40x<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=6cm ALIGN=MIDDLE  ALT=\"x=6cm\"   DISABLED_style= \"max-width:90%; height:auto;\" > = upper base<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10%2B6=16cm ALIGN=MIDDLE  ALT=\"10%2B6=16cm\"   DISABLED_style= \"max-width:90%; height:auto;\" > = lower base<BR>\n" );
document.write( "In doubt? to go back to our eqn and you'll see, A=(1/2)(h)(a+b)<BR>\n" );
document.write( "thank you,<BR>\n" );
document.write( "Jojo </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );