(х-5 3/4)*2+9 7/11=12
(х-5 3/4)*2=12-9 7/11 12-9 7/11=11 11/11-9 7/11=2 4/11
(х-5 3/4)*2=2 4/11
х-5 3/4=2 4/11:2 2 4/11:2=26/11*1/2=13/11=1 2/11
x-5 3/4=1 2/11
x=1 2/11+5 3/4 1 2/11+5 3/4=1 8/44+5 33/44=6 41/44
x=6 41/44
проверка (6 41/44-5 3/4)*2+9 7/11=12
1 2/11*2+9 7/11=12
2 4/11+9 7/11=12
12=12