x+3/20=5/12+2/9 .......

х=23/36-3/20х=22/45ответ: х=22/45

x + 3\20 = 5\12 + 2\9 5\12 + 2\9 = 15\36 + 8\36 = 23\36x + 3\20 = 23\36x = 23\36 - 3\20 = 460\720 - 108\720 = 352\720 = 176\360= 88\180 =44\90 = 22\45x = 22\4522\45 + 3\20 = 440\900 + 135\900 = 575\900 =23\36