Factorise the following :
 
\(9x^2 + 4y^2 + 16z^2 + 12xy – 16yz – 24xz\)
Answer variants:
\((4x-2y+3z)^2\)
\((4x-2y-3z)^2\)
\((3x-4y-4z)^2\)
\((3x+4y-4z)^2\)
\((5x+4y-2z)^2\)
\((-5x+4y+2z)^2\)