2 9× 7 4=× 1 7 July 8, 2019 16 32 64 128 X 7 4 2 9 1 7 1 7 9 2 4 7 7 9x 4 1 2 x 9 7x 3 7w 2 9 4 9w 1 7 3 7x 2 9 4 9x 1 7 2 3x 1 3x 4 7 9 7 Tìm xax 7 4 2 9 1 7 2 9×+7 4=×+1 7 7 9+2 2 7 2/9+4
