document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=383752>Question 383752</A>: <I><SPAN STYLE=\"word-break: break-all;\"> why does a trapezoid can only have at most two interior angles? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #272308 by </B><A HREF=/tutors/aboutme.mpl?userid=mtmorro><B>mtmorro(23)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mtmorro><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=mtmorro><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=272308\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Both have one pair of parallel sides, but by definition, a rectangle is NOT a trapezoid since a trapezoid can have ONLY one set of parallel sides and a rectangle always has two. this keeps it from <BR>\n" );
document.write( "actually being a rectangle \r<BR>\n" );
document.write( "\n" );
document.write( "A trapezoid is a quadrilateral having one pair of parallel sides.\r<BR>\n" );
document.write( "\n" );
document.write( "Parallel sides of trapezoid are base sides and distance between parallel sides is height of trapezoid.\r<BR>\n" );
document.write( "\n" );
document.write( "Area of trapezoid is given as product of average of base sides and height of trapezoid.\r<BR>\n" );
document.write( "\n" );
document.write( "Area= 21(Sum of base sides) X height\r<BR>\n" );
document.write( "\n" );
document.write( "A trapezoid is a quadrilateral having one pair of parallel sides.\r<BR>\n" );
document.write( "\n" );
document.write( "Parallel sides of trapezoid are base sides and distance between parallel sides is height of trapezoid.\r<BR>\n" );
document.write( "\n" );
document.write( "Area of trapezoid is given as product of average of base sides and height of trapezoid.\r<BR>\n" );
document.write( "\n" );
document.write( "Area= 21(Sum of base sides) X height\r<BR>\n" );
document.write( "\n" );
document.write( "Here A, B, C and D are four vertices of trapezoid. AB and CD are parallel sides and BC and DA are non-parallel sides. Length AB is ‘a’ and that of CD is ‘b’.\r<BR>\n" );
document.write( "\n" );
document.write( "Area= 21 (a + b)h\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "Properties of Trapezoid<BR>\n" );
document.write( "1. It must have four sides, four corners and two diagonal.\r<BR>\n" );
document.write( "\n" );
document.write( "2. The sum of interior angles is 360 degrees.\r<BR>\n" );
document.write( "\n" );
document.write( "3. Angle adjacent to opposite bases are supplementary.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "4. It has one pair of parallel sides.\r<BR>\n" );
document.write( "\n" );
document.write( "5. It has median(line equidistant from parallel sides) whose length is given as \frac12 X Sum of parallel sides.\r<BR>\n" );
document.write( "\n" );
document.write( "6. length of any line parallel to parallel sides can be calculated as-\r<BR>\n" );
document.write( "\n" );
document.write( "    EF is parallel to AB\r<BR>\n" );
document.write( "\n" );
document.write( "    EF = [kX(CD)]+[mX(AB)](AD)\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "Isosceles trapezoid<BR>\n" );
document.write( "If the two non-parallel sides have equal lengths, then the trapezoid is called an isosceles trapezoid.\r<BR>\n" );
document.write( "\n" );
document.write( "Properties of Isosceles trapezoid\r<BR>\n" );
document.write( "\n" );
document.write( " 1. Isosceles trapezoid has exactly one line of symmetry and that is the line joining mid-point of parallel sides. So, basically this line is dividing it again into two trapezoids.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " 2. Base angles of isosceles trapezoid have same measure.\r<BR>\n" );
document.write( "\n" );
document.write( "     Here If 1 and  2 are base angles.\r<BR>\n" );
document.write( "\n" );
document.write( "     So, If 1 =  2\r<BR>\n" );
document.write( "\n" );
document.write( "     And also angle DAB =angle  DCB\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " 3. Opposite angles are supplementary.\r<BR>\n" );
document.write( "\n" );
document.write( " 4. The diagonals of trapezoid have same length.\r<BR>\n" );
document.write( "\n" );
document.write( " 5. On the extension of non-parallel side isosceles triangle is formed.\r<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );