Question

- 9 (8 - 9 х) = 4 х + 5

Answer 1

-9(8-9х)=4х+5
-72+81х=4х+5
81х-4х=5+72
77х=77
х=77:77
х=1
Проверка
-9(8-9*1)=4*1+5
-9*(-1)=4+5
9=9

Answer 2

- 9 (8 - 9 х) = 4 х + 5
-72 + 81х = 4х + 5
-72-5 = 4х -81х
-77 = -77х
х = 1