5 - ( 12 - x ) = 129 - ( 6 + 129 )
5 - 12 + x = 129 - 6 - 129
( -7 ) + x = ( -6)
x = ( - 6 ) + 7
x = 1
Vậy x = 1
5-(12-x)=129-(6+129)
5-(12-x)=129-135
5-(12-x)=-6
12-x =5-(-6)
12-x=11
x=12-11
x=1
5 – ( 12 – x ) = 129 – ( 6 + 129 )
5-(12-x)=129-135
5-(12-x)=-6
(12-x)=5-(-6)
12-x=11
x=12-11
x=1
vay x=1