213-(76+а)=56 86+(141-х)=350 57-у=19 m-235=248 У+98=162 (78+х)-64=59 (Х-273)+96=296

№1213 - (76 + а) = 56;213 – 56 = 76 + а;157 = 76 + а;а = 157 – 76;а = 81.Проверка:213 – (76 + 81) = 56;213 – 157 = 56;56 = 56.№286 + (141 - х) = 350;141 – х = 350 – 86;141 – х = 264;-х = 123;х = -123.Проверка:86 + (141 – (-123)) = 350;86 + 141 + 123 = 350;350 = 350.№357 – у = 19;-у = 19 – 57;у = 57 – 19;у = 38.Проверка:57 – 38 = 19;19 = 19.№4m – 235 = 248;m = 248 + 235;m = 483.483 – 235 = 248;248 = 248.№5у + 98 = 162;у = 162 – 98;у = 64.Проверка:64 + 98 = 162;162 = 162.№6(78 + х) – 64 = 59;78 + х = 59 + 64;78 + х = 123;х = 123 – 78;х = 45.Проверка:(78 + 45) – 64 = 59;123 – 64 = 59;59 = 59.№7(х - 273) + 96 = 296;х – 273 = 296 – 96;х – 273 = 200;х = 200 + 273;х = 473.Проверка:(473 - 273) + 96 = 296;200 + 96 = 296;296 = 296.