Question

factorise the following:z-7+7xy-xyz

Answer 1

z-7+7xy-xyz
=1(z-7)-xy(z-7)
=(z-7)(1-xy)

Answer 2

Answer: z-7+7xy-xyz

            -=  (z-xyz)+(-7+7xy)

             = z(1-xy) -7(1-xy)

              = (z-7)(1-xy)