6 5 3 8x 9 July 8, 2019 16 32 64 128 9x 5 (- 8x 3 )- 6 =- 21 5 2x 6 )+ 2 4x 3 )= 8x 9 9x 5 (- 8x 3 )- 6 6 8+5 9 6 5×(-30 8) 6 8+3 5