54:х + 11 = 800 : 4054:х+11 = 20 54:х = 20 - 1154:х = 9х= 54 : 9 х=6----------------------------54 : 6 + 11 = 800:409 + 11 = 2020=20х*5 +12*9 = 1385х + 108 = 1385х = 138 - 1085х = 30х = 30:5х=6---------------------6 * 5 + 12*9 = 13830 +108 = 138138=138120 + х*3 = 375х*3 = 375 - 1203х = 255х= 255 :3х = 85 -----------------------120 + 85 *3 =375120 +255=375375=375600 - 120 +х*6 =6006х = 600-600 + 1206х =120х=120:6х= 20--------------------------------600 - 120 + 20*6 = 600600 - 120 + 120 = 600600=6001260 +2х=30002х = 3000 - 12602х =1740х=1740 :2х= 870---------------------------1260 + 2*870 = 30001260 +1740=30003000=3000