( (22/7)х + (11/2) )* 18/11 =21
( (22/7)х + (11/2) )= 21 : 18/11
( (22/7)х + (11/2) )= 21/1 * 11/18= (22*11)/(1*18) →(сокр на 3 →21/18=7/6)
( (22/7)х + (11/2) )=(7*11)/6
( (22/7)х + (11/2) )=77/6
(22/7)х + 11/2=77/6
(22/7)х= 77/6 - 11/2= (77*1)/ 6 - (11*3)/(2*3)= (77-33)/6= 44/6=22/3
х= 22/3 :22/7
х= 22/3 *7/22= (22*7)/(3*22) сокрашаем 22/22=1
х= 7/3= 2_1/3
ответ х= 2_1/3