1) 139+ (67-7х) =199

139+ 67-7х =199

-7х =199-139-67

-7х =-7

х=1

2) 17 - ( 3х + 1 ) = 4

17 - 3х - 1 = 4

- 3х = 4-17+1

- 3х =-12

х=4