Răspuns :
(x+214)-253= 256
x+214= 256+253
x+214= 509
x= 509-214
x= 295
PROBA:
(295+214)-253= 256
509-253= 256
256= 256
x+214= 256+253
x+214= 509
x= 509-214
x= 295
PROBA:
(295+214)-253= 256
509-253= 256
256= 256