1 7 x 4 9 10 July 8, 2019 16 32 64 128 1 7 x + 4 9 10 1 3 7 х 4 9 10 1 4 5 x 2 2 7 x 10 9 1 4 x 7 1 7 x +4 9=10 1 7 × +4 9=10