X square minus y square 2 yz z square July 8, 2019 16 32 64 128 The expression x square minus y square z square 2 yz x y z has a factor 4 x square 12 x minus y square z square minus 2 yz 9 square Factorise 4 x square + y square + z square - 4 x minus 2yz + 4xz