Question

(x+27)-12=42 115-(35-y)=39

Answer 1

(x+27)-12=42

Х+27=42+12

Х=54-27

Х=27

 

115-(35-y)=39

35-У=115-39

У=35-76

У=-41

Answer 2

(х+27)-12=42

х+27=42+12

х+27=54

х=54-27

х=27

проверка

(27+27)-12=42

54-12=42

42=42

==================================

115-(35-у)=39

-35+у=39-115

-35+у=-76

у=-76+35

у=-41

проверка

115-(35-(-41))=39

115-76=39

39=39