478 - (256 + x) = 143
478 - 256 - x = 143
222 - x = 143
-x = -79
x = 79
Therefore, the value of x is 79.
478 - (256 + x) = 143
478 - 256 - x = 143
222 - x = 143
-x = -79
x = 79
Therefore, the value of x is 79.