document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1153532>Question 1153532</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It took 72 square feet of Tyvek house wrap to cover a trapezoid-shaped part of a house. Find the height of the trapezoid if the length of its shorter base is the same as its height. (The formula for the area of a trapezoid is <BR>\n" );
document.write( "A = 1/2 h (b (sub) 1 + b (sub) 2)<BR>\n" );
document.write( ", where h is its height, and b1 and b2 are the lengths of the two bases.)\r<BR>\n" );
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document.write( "FInd the height!<BR>\n" );
document.write( "There is a little illustration of a trapezoid that says the longest base is 18 ft. If you want to see the illustration, reply to me wiht your email and ill send it your way. Thank you! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #775776 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=775776\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "The answer is <font color=red>6 feet</font>\r<BR>\n" );
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document.write( "How to get this answer:\r<BR>\n" );
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document.write( "h = height<BR>\n" );
document.write( "b1 = longer base = 18 ft<BR>\n" );
document.write( "b2 = shorter base = h<BR>\n" );
document.write( "A = area of trapezoid = 72 square ft\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+%28h%2A%28b1%2Bb2%29%29%2F2 ALIGN=MIDDLE  ALT=\"A+=+%28h%2A%28b1%2Bb2%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > area of trapezoid formula\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=72+=+%28h%2A%2818%2Bh%29%29%2F2 ALIGN=MIDDLE  ALT=\"72+=+%28h%2A%2818%2Bh%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > plug in given values\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=72%2A2+=+h%2A%2818%2Bh%29 ALIGN=MIDDLE  ALT=\"72%2A2+=+h%2A%2818%2Bh%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply both sides by 2\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=144+=+18h%2Bh%5E2 ALIGN=MIDDLE  ALT=\"144+=+18h%2Bh%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Distribute\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0+=+18h%2Bh%5E2-144 ALIGN=MIDDLE  ALT=\"0+=+18h%2Bh%5E2-144\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract 144 from both sides\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0+=+h%5E2%2B18h-144 ALIGN=MIDDLE  ALT=\"0+=+h%5E2%2B18h-144\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h%5E2%2B18h-144+=+0 ALIGN=MIDDLE  ALT=\"h%5E2%2B18h-144+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > Get equation into standard form\r<BR>\n" );
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document.write( "Use the quadratic formula to solve for h<BR>\n" );
document.write( "We will plug in: a = 1, b = 18, c = -144\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"h+=+%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"h+=+%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+%28-18%2Bsqrt%28%2818%29%5E2-4%281%29%28-144%29%29%29%2F%282%281%29%29 ALIGN=MIDDLE  ALT=\"h+=+%28-18%2Bsqrt%28%2818%29%5E2-4%281%29%28-144%29%29%29%2F%282%281%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+%28-18-sqrt%28%2818%29%5E2-4%281%29%28-144%29%29%29%2F%282%281%29%29 ALIGN=MIDDLE  ALT=\"h+=+%28-18-sqrt%28%2818%29%5E2-4%281%29%28-144%29%29%29%2F%282%281%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+%28-18%2Bsqrt%28900%29%29%2F%282%29 ALIGN=MIDDLE  ALT=\"h+=+%28-18%2Bsqrt%28900%29%29%2F%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+%28-18-sqrt%28900%29%29%2F%282%29 ALIGN=MIDDLE  ALT=\"h+=+%28-18-sqrt%28900%29%29%2F%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+%28-18%2B30%29%2F%282%29 ALIGN=MIDDLE  ALT=\"h+=+%28-18%2B30%29%2F%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+%28-18-30%29%2F%282%29 ALIGN=MIDDLE  ALT=\"h+=+%28-18-30%29%2F%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+%2812%29%2F%282%29 ALIGN=MIDDLE  ALT=\"h+=+%2812%29%2F%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+%28-48%29%2F%282%29 ALIGN=MIDDLE  ALT=\"h+=+%28-48%29%2F%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+6 ALIGN=MIDDLE  ALT=\"h+=+6\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+-24 ALIGN=MIDDLE  ALT=\"h+=+-24\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Ignore the negative solution for h. A negative height does not make sense.\r<BR>\n" );
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document.write( "The only possible height value is h = 6.<BR>\n" );
document.write( "Therefore, the shorter base is also 6 ft long.\r<BR>\n" );
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document.write( "Let's check to see if b1 = 18, b2 = 6, and h = 6 all lead to an area of 72<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+%28h%2A%28b1%2Bb2%29%29%2F2 ALIGN=MIDDLE  ALT=\"A+=+%28h%2A%28b1%2Bb2%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+%286%2A%2818%2B6%29%29%2F2 ALIGN=MIDDLE  ALT=\"A+=+%286%2A%2818%2B6%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+%286%2A24%29%2F2 ALIGN=MIDDLE  ALT=\"A+=+%286%2A24%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+144%2F2 ALIGN=MIDDLE  ALT=\"A+=+144%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+72 ALIGN=MIDDLE  ALT=\"A+=+72\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The answer is confirmed.\r<BR>\n" );
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document.write( "</font> </SPAN>\n" );
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