document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=849366>Question 849366</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Given that triangle ABC is similar to triangle FED,where AB = 77,EF = 21, BC = 11x + 11, and DE = 30.Find x. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #511540 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=511540\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> if the triangles are similar, then the sides are proportional.\r<BR>\n" );
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document.write( "this means that AB  / EF = BC / DE\r<BR>\n" );
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document.write( "AB= 77<BR>\n" );
document.write( "EF = 21<BR>\n" );
document.write( "BC = 11x + 11<BR>\n" );
document.write( "DE = 30\r<BR>\n" );
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document.write( "ratio becomes:\r<BR>\n" );
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document.write( "77 / 21 = (11x + 11) / 30\r<BR>\n" );
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document.write( "multiply both sides of this equation by 30 and you get:\r<BR>\n" );
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document.write( "(77 * 30) / 21 = 11x + 11\r<BR>\n" );
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document.write( "simplify this to get:\r<BR>\n" );
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document.write( "110 = 11x + 11\r<BR>\n" );
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document.write( "subtract 11 from both sides of this equation to get:\r<BR>\n" );
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document.write( "99 = 11x\r<BR>\n" );
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document.write( "divide both sides of this equation by 11 to get:\r<BR>\n" );
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document.write( "9 = x\r<BR>\n" );
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document.write( "that's your answer.\r<BR>\n" );
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document.write( "11x + 11 is equal to 99 + 11 is equal to 110.\r<BR>\n" );
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document.write( "the ratio of:\r<BR>\n" );
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document.write( "77 / 21 = (11x + 11) / 30 becomes:\r<BR>\n" );
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document.write( "77 / 21 = 110 / 30\r<BR>\n" );
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document.write( "cross multiply to get 77 * 30 = 21 * 110\r<BR>\n" );
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document.write( "simplify to get 2310 = 2310, confirming the solution of x = 9 is good.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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