2 1 4x3 7 July 8, 2019 16 32 64 128 2 1 4 x 3 7 2 1 4 x 3 7 9 9 3 4 x 7 1 2 notebook 4 7 x 2 3 =- 1 5 4 x 3 )= 7 2 1 10 7 1 4 x 11 2 3 4 y 1 2 =- 7 x 3 2 7 12 x 4 1 3 4 7 x 5 6 1 2 3 4 1/2 + 1 1/3 7 1/2 x 4 7 1/2 x 2 3/4