a, ( -11 )x = 10 . ( -5 ) - 5
( -11 )x = -50 - 5
( -11 )x = -55
x = ( -55 ) : ( -11 )
x = 5
Vậy x = 5
b, ( -2 ) . x - 4 = 4 . ( -7 ) + 4
( -2 ) . x - 4 = -28 + 4
( -2 ) . x - 4 = -24
( -2 ) . x = -24 + 4
( -2 ) . x = -20
x = ( -20 ) : ( -2 )
x = 10
Vậy x = 10
c, 2x + 1 = -3
2x = -3 - 1
2x = -4
x = ( -4 ) : 2
x = -2
Vậy x = -2
d, ( -3 ) . x + 3 = -24
( -3 ) . x = -24 - 3
( -3 ) . x = -27
x = ( -27 ) : ( -3 )
x = 9
Vậy x = 9