7 (- 6 x )- 4x =- 9 July 8, 2019 16 32 64 128 3x 6 x 7 9 4x 3 14 7 2 x 3 6 9 4x 8 9x 7 4x 4 6 x 1 )- 9 6xy - 4y + 6 - 9x
