[a+(1308:12)×3]-1000:100=8255. (a+109)×3-10=8255. (a+109)×3=8255+10. (a+109)×3=8265. a+109=8265:3. a+109=2755. a=2755-109. a=2646. b)1440+250×9-x=2507. 1440+2250-x=2507. inlocuim2250-x cu b si avem. 1440+b=2507. b=2507-1440. b=1167. 2250-x=1167. x=2250-1167. x=1183