(2+х/7)*8=72
(2+x/7)*8=72
(2+x/7)=9
x/7=9-2
x/7=7
x=7*7
x=49
(2+x/7)*8=72 /:8
(2+x/7)= 72 : 8
( 2 + x/7) =9 /-2
x/7 = 9-2
x/7 = 7 /*7
x = 7 * 7