document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=189870>Question 189870</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve the missing base of a trapezoid.<BR>\n" );
document.write( "The area is 780cm.The height is 8.The shorter base is 48 cm.\r<BR>\n" );
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document.write( "Also,help me find the height of a triangle with area 85 1/3 ft. and base is 10 2/3 ft.\r<BR>\n" );
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document.write( "THANKS!. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #142605 by </B><A HREF=/tutors/aboutme.mpl?userid=schrammbledeggs><B>schrammbledeggs(41)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=schrammbledeggs><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=142605\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The formula for area of a trapezoid is: \r<BR>\n" );
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document.write( "Area = height ( (base1 + base2) / 2)\r<BR>\n" );
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document.write( "So let's plug in what we know:\r<BR>\n" );
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document.write( "780cm = 8( base1 + 48cm) / 2)\r<BR>\n" );
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document.write( "We can divide by 8 at first:\r<BR>\n" );
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document.write( "780/8 = (base1 + 48cm) /2<BR>\n" );
document.write( "97.5cm = (base1 + 48cm) /2\r<BR>\n" );
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document.write( "Now we can multiply both sides by 2:\r<BR>\n" );
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document.write( "97.5cm *2 = (base1 + 48cm) / 2 *2<BR>\n" );
document.write( "195cm = base 1 + 48 cm\r<BR>\n" );
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document.write( "Subtract 48cm from both sides:\r<BR>\n" );
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document.write( "195cm - 48cm = base1 + 48cm - 48cm<BR>\n" );
document.write( "147cm = base1\r<BR>\n" );
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document.write( "Now...area of a triangle:\r<BR>\n" );
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document.write( "A = 1/2 * b * h\r<BR>\n" );
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document.write( "Let's plug in what we're given after changing mixed numbers to improper fractions:\r<BR>\n" );
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document.write( "85 1/3 ft = 256/3 ft<BR>\n" );
document.write( "10 2/3 ft = 32/3 ft\r<BR>\n" );
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document.write( "256/3 ft = 1/2 * 32/3 * h<BR>\n" );
document.write( "256/3 ft = 32/6 * h\r<BR>\n" );
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document.write( "Multiply both sides by the reciprocal of 32/6...which is 6/32 to isolate h:\r<BR>\n" );
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document.write( "256/3 ft * 6/32 = 32/6 * h * 6/32<BR>\n" );
document.write( "1536/96 ft = h\r<BR>\n" );
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document.write( "Reduced into lowest terms:\r<BR>\n" );
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document.write( "16 ft = h\r<BR>\n" );
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document.write( ":)<BR>\n" );
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