(52-х)+43=78 123-(37+а)=15 169+(37+а)=235 (52+х)+43=178 354-(177+а)=93

№1(52 - х) + 43 = 78;52 – х = 78 – 43;52 – х = 35;- х = 35 – 52;х = 52 – 35;х = 17.Проверка:(52 – 17) + 43 = 78;35 + 43 = 78;78 = 78.№2123 - (37 + а) = 15;123 – 15 = 37 + а;108 = 37 + а;а = 108 – 37;а = 71.Проверка:123 – (37 +71) = 15;123 – 108 = 15;15 = 15.№3169 + (37 + а) = 235;37 + а = 235 – 169;37 + а = 66;а = 66 – 37;а = 29.Проверка:169 + (37 +29) = 235;169 + 66 = 235;235 = 235.№4(52 + х) + 43 = 178;52 +х = 178 – 43;52 + х = 135;х = 135 – 52;х = 83.Проверка:(52 + 83) + 43 = 178;135 + 43 = 178;178 = 178.№5354 - (177 + а) = 93;354 – 93 = 177 + а;261 = 177 + а;а = 261 – 177;а = 84.Проверка:354 – (177 + 84) = 93;354 – 261 = 93;93 = 93.