10x 9 - 3 2 5x July 8, 2019 16 32 64 128 9 10x 3 2 5x 4 5x 25x 2 10x 3 9 (- 10x 2 4x 3 )-( 5x 2 4x 9 10 + 5(9x - 9) 10 x 10 x 10 5 x 9