( 72 - 64 : ( 40 - 8х )) : 4 = 256
72 - 64 : (40 - 8x ) = 256 * 4
72 - 64 : (40 - 8x ) = 1024
- 64 : (40 - 8x ) = 1024 - 72
- 64 : (40 - 8x ) = 952
40 - 8x = -64 : 952
40 - 8x = -8/119
8x = 40 + 8/119
8x=40 8/119
x=40 8/119 : 8
x=4768/119 * 1/8
x=596/119
x= 5 1/119