Пошаговое объяснение:
(7/9х + 2. 5/9) : 5/9 = 8. 1/10
7/9х + 2. 5/9 = 81/10 * 5/9
7/9х + 2. 5/9 = 9/2 * 1/1
7/9х + 2. 5/9 = 9/2
7/9х + 2. 5/9 = 4. 1/2
7/9x = 4. 1/2 - 2. 5/9
7/9х = 4. 9/18 - 2. 10/18
7/9х = 3. 27/18 - 2. 10/18
7/9х = 1. 17/18
х = 1. 17/18 : 7/9
х = 35/18 * 9/7
х = 5/2 * 1/1
х = 5/2
х = 2. 1/2
