9x 9 6x 1 July 8, 2019 16 32 64 128 9x 9 6x 18 9x 9 6x 6 180 9x 9 5 =- 12 6x 6x 9 9x 15 4x 3x 9x 11 6x 9 6x 9 9x 15 9x 12 6x 9 9x 2y 39 6x 13y =- 9 elimination 18 3x 11 9x 9 6x 6 9x 6x 10x 9