\(25-\left(25-x\right)=12+\left(42-65\right).\)
\(\Leftrightarrow25-25+x=12-23.\)
\(\Leftrightarrow x=-11.\)
Vậy \(x=-11.\)
25 - ( 25 - x ) = 12 + ( 42 - 65 )
25 - ( 25 - x ) = 12 + (-23)
25 - ( 25 - x ) = -11
25 - x = 25 - (-11)
25 - x = 36
x = 25 - 36
x = -11
25−(25−x)=12+(42−65).25−(25−x)=12+(42−65).
⇔25−25+x=12−23.⇔25−25+x=12−23.
⇔x=−11.⇔x=−11.
Vậy x=−11.