(829 - х) + 365 = 514
829 - х = 514 - 365
829 - х = 149
х = 829 - 149
х = 680
Проверка :
(829 - 680) + 365 = 514
149 + 365 = 514
514 = 514
4.....................................................
2+2+2+2+2+2+2+2+2 = <span>2*9
</span>2+2+2+2 = <span>2*4
</span>2+2+2+2+2+2 = <span>2*6
2+2 = </span><span>2*2
2+2+2+2+2 = </span><span>2*5
</span>2+2+2+2+2+2+2 = <span>2*7</span>