\r\n" );
document.write( "Note: the word is \"perimeter\", not \"parameteras\", as you had it.\r\n" );
document.write( "\"Perimeter\" means the distance all the way around a figure.\r\n" );
document.write( "\r\n" );
document.write( "I corrected that :-)\r\n" );
document.write( "
\n" );
document.write( "The parallel sides of trapezoid ABCD are 3 cm and 9 cm(AB and DC).The non parallel sides are 4 cm and 6 cm(AD and BC).A line(PQ) parallel to base(DC) divides the trapezoid into two trapezoids(ABQP and PQCD ) of equal perimeters. Find the ratio in which each of the non parallel sides is divided,if AP:BQ=PD:QC
\n" );
document.write( "\r\n" );
document.write( "Here's the trapezoid:\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Now we'll draw in PQ parallel to the top and bottom of the trapezoid,\r\n" );
document.write( "cutting it into two trapezoids with equal perimeters. \r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( " \r\n" );
document.write( "Now I'll explain my labeling of those parts:\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Divide both sides by
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Take reciprocals of both sides\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Add 1 to both sides\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Replace 1 by
on the left and replace 1 on the right by
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Combine numerators over denominators:\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Since AP+PD = AD = 6 and BQ+QC = BC = 4\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Take reciprocals of both sides\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Let that ratio be = k\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "
and
\r\n" );
document.write( "\r\n" );
document.write( "BQ = 4k,\r\n" );
document.write( "QC = 4 - 4k\r\n" );
document.write( "AP = 6k\r\n" );
document.write( "PD = 6 - 6k \r\n" );
document.write( " \r\n" );
document.write( "all in centimeters. \r\n" );
document.write( " \r\n" );
document.write( "Perimeter of the upper trapezoid ABQP:\r\n" );
document.write( "\r\n" );
document.write( "BQ + AB + AP + PQ\r\n" );
document.write( "\r\n" );
document.write( "Perimeter of the lower trapezoid PQCD:\r\n" );
document.write( "\r\n" );
document.write( "QC + DC + PD + PQ\r\n" );
document.write( "\r\n" );
document.write( "Equating the two perimeters:\r\n" );
document.write( "\r\n" );
document.write( "BQ + QB + AP + PQ = QC + DC + PD + PQ\r\n" );
document.write( "\r\n" );
document.write( "Subtract PQ (their common side) from both sides:\r\n" );
document.write( "\r\n" );
document.write( " BQ + QB + AP = QC + DC + PD\r\n" );
document.write( "\r\n" );
document.write( "Substitute their lengths in terms of the fraction k:\r\n" );
document.write( " \r\n" );
document.write( " 4k + 3 + 6k = (4-4k) + 9 + (6-6k)\r\n" );
document.write( "\r\n" );
document.write( " 10k + 3 = 4 - 4k + 9 + 6 - 6k\r\n" );
document.write( "\r\n" );
document.write( " 10k + 3 = 19 - 10k\r\n" );
document.write( " \r\n" );
document.write( " 20k = 16\r\n" );
document.write( "\r\n" );
document.write( " k =
=
= 0.8\r\n" );
document.write( "\r\n" );
document.write( "Therefore\r\n" );
document.write( "\r\n" );
document.write( "AP = 6k = 6(0.8) = 4.8 cm. \r\n" );
document.write( "\r\n" );
document.write( "BQ = 4k = 4(0.8) = 3.2 cm. \r\n" );
document.write( "\r\n" );
document.write( "PD = 6-6k = 6-6(0.8) = 1.2 cm.\r\n" );
document.write( "\r\n" );
document.write( "QC = 4-4k = 4-4(0.8) = 0.8 cm\r\n" );
document.write( "\r\n" );
document.write( "We want to find\r\n" );
document.write( "\r\n" );
document.write( "AP:PD = BQ:QC\r\n" );
document.write( "\r\n" );
document.write( "which is 4.8:1.2 = 48:12 = 4:1\r\n" );
document.write( "\r\n" );
document.write( "and checking:\r\n" );
document.write( "\r\n" );
document.write( "BQ:QC = 3.2:0.8 = 32:8 = 4:1\r\n" );
document.write( "\r\n" );
document.write( "That's the answer 4:1\r\n" );
document.write( "\r\n" );
document.write( "Incidentally, the figures above are drawn approximately to scale.\r\n" );
document.write( "Measure them with a ruler and you will see they are fairly close to\r\n" );
document.write( "3cm, 4cm, 9cm and 6cm.\r\n" );
document.write( " \r\n" );
document.write( "The perimeters are equal even though the upper trapezoid is obviously \r\n" );
document.write( "lots bigger in area. This demonstrates the important fact that two\r\n" );
document.write( "figures can have the same perimeter and quite different areas. \r\n" );
document.write( "\r\n" );
document.write( "Edwin
\n" );
document.write( " \n" );
document.write( "