Решите уравнения двумя способами, (х+27) - 12=42,115 - (35+у) = 39

(х+27) - 12=42 (х+27) - 12=42

x-27-12=42 x-27-12=42

x=42+27+12 x-39=42

x=81 x=42+39

x=81

115 - (35+у) = 39 115 - (35+у) = 39

115-35-y=39 115-35-y=39

-y=39-115+35 80-y=39

-y=-41 - y=39-80

y=-41: (-1) - y=-41

y=41 y=-41: (-1)

y=41