document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1117221>Question 1117221</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A region of land,50 meter by 40 meter is to cross diagonally by a road 15 meters wide. What is the road`s area?\r<BR>\n" );
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document.write( "Answer: 844.8 square meter\r<BR>\n" );
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document.write( "I really don`t know the solution. Please explain. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #732235 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=732235\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A region of land,50 meter by 40 meter is to cross diagonally by a road 15 meters wide. What is the road`s area? <BR>\n" );
document.write( " Answer: 844.8 square meter <BR>\n" );
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document.write( "Some info is missing, assumptions are made.<BR>\n" );
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document.write( "Assuming the centerline of the road is the diagonal:<BR>\n" );
document.write( "Use the rectangle with points (0,0), (0,40), (50,40) and (50,0)<BR>\n" );
document.write( "The diagonal line has an equation y = 4x/5 = 0.8x<BR>\n" );
document.write( "The length of the diagonal is 10sqrt(41) meters<BR>\n" );
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document.write( "Using some trig, the lines parallel to the diagonal and 7.5 meters from it are<BR>\n" );
document.write( "y = 0.8x + sqrt(41) and<BR>\n" );
document.write( "y = 0.8x - sqrt(41)<BR>\n" );
document.write( "The 2 areas above and below the centerline are equal.<BR>\n" );
document.write( "--> Area of 1 side = 10sqrt(41)*7.5 - the areas of the 2 triangles formed.<BR>\n" );
document.write( "The area of the smaller triangle = 7.5*0.8*7.5/2 = 22.5 sq meters.<BR>\n" );
document.write( "The area of the larger triangle = 7.5*1.25*7.5/2 = 35.15625 sq meters.<BR>\n" );
document.write( "2 triangles' area = 57.65625 sq meters<BR>\n" );
document.write( "--------<BR>\n" );
document.write( "Area of each side = 10sqrt(41)*7.5 - 57.5625 = 422.578 sq meters<BR>\n" );
document.write( "Times 2 = 845.156 sq meters<BR>\n" );
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document.write( "That's close to the stated area.<BR>\n" );
document.write( "IDK how the given answer was derived.\r<BR>\n" );
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