\r\n" );
document.write( "<5,6> and <2,3x>\r\n" );
document.write( "\r\n" );
document.write( "To be parallel one must be a multiple of the other:\r\n" );
document.write( "\r\n" );
document.write( "<5,6> = k<2,3x>\r\n" );
document.write( "\r\n" );
document.write( "<5,6> = <2k,3kx>\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "For the first equation k =
\r\n" );
document.write( "\r\n" );
document.write( "Substitute in the second equation:\r\n" );
document.write( "\r\n" );
document.write( "6 = 3(
)x\r\n" );
document.write( "\r\n" );
document.write( "12 = 3(5x)\r\n" );
document.write( "\r\n" );
document.write( "12 = 15x\r\n" );
document.write( "\r\n" );
document.write( "
= x\r\n" );
document.write( "\r\n" );
document.write( "
= x\r\n" );
document.write( "\r\n" );
document.write( "--------------------------\r\n" );
document.write( "\r\n" );
document.write( "<5,6> and <2,3x>\r\n" );
document.write( "\r\n" );
document.write( "To be orthogonal their dot product must be 0:\r\n" );
document.write( "\r\n" );
document.write( " <5,6>•<2,3x> = 0\r\n" );
document.write( "\r\n" );
document.write( "(5)(2)+(6)(3x) = 0\r\n" );
document.write( "\r\n" );
document.write( " 10+18x = 0\r\n" );
document.write( "\r\n" );
document.write( " 18x = -10\r\n" );
document.write( "\r\n" );
document.write( " x =
\r\n" );
document.write( "\r\n" );
document.write( " x =
\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "----------------------------------\r\n" );
document.write( "\r\n" );
document.write( "To be neither, choose x as anything other than those two values.\r\n" );
document.write( "\r\n" );
document.write( "Edwin
\n" );
document.write( "