\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Draw the two right triangles congruent. \r\n" );
document.write( "The angle indicated by the counter-clockwise red arc is A.\r\n" );
document.write( "The angle indicated by the clockwise green arc is A-180°.\r\n" );
document.write( "The values of x and y are positive, and r is ALWAYS taken positive.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( " \r\n" );
document.write( "\r\n" );
document.write( "So proved geometrically.\r\n" );
document.write( "\r\n" );
document.write( "Edwin