15 3 x 7 2 July 8, 2019 16 32 64 128 15 3x 3 )- 7 24 13x )=- 98 15 2x 3 7 x 15 2 x 3 7 4 5 2 15 7 9 7 x 2 3 4 x 3 )- 15 2 x 7 )- 15x 3 x 7 )- 15 27 15 3 x 7 2 x 3 8 2 15 x 7 4 3 2 1 4 3 7 x 21 15 3 7 x 15 2x 0 15 7 x 3 20 7 15 x 3 28 X 7 y 15 3 x 2 y 5 4 15 x 2 7 x 3 6