kittenkitten16 (x+27) - 12 = 42
x+27=42+12
x=54-27
x=27
ответ 27
115 - (35+y) = 39
115 - 35 - y = 39
-y=39-115+35
-y=-41
y = 41

greatnast123 X+27-12=42
X+15=42
X=42-15
X=27


115-35-y=39
80-y=39
Y=41