7x x 3 21 July 8, 2019 16 32 64 128 X 3 7x 2 21x 27 7 x 3 )= 7x 21 X 3 7x 2 21x 27 0 X 3 3x 2 7x 21 X 3 3x 2 7x 21 0 7x 21 x 2 x 3 5 X x 3 )- 7x 21 0 Factorise x 3 7x 2 21x 27 2x 7