- 12 + 3 ( - x + 7 ) = - 18
3 ( - x + 7 ) = ( - 18 ) + 12
3 ( - x + 7 ) = - 6
- x + 7 = ( - 6 ) : 3
- x + 7 = - 2
- x = ( - 2 ) - 7
- x = - 9
=> x = 9
^^ Cbht!!!
-12+3(-x+7)=-18
3(-x+7)=-18-(-12)
-3x+21=-6
-3x=-6-21
-3x=-24
x=-24:(-3)
x=8
Vậy x=8
\(-12+3\left(-x+7\right)=-18\)
\(\Rightarrow3\left(-x+7\right)=-18+12=-6\)
\(\Rightarrow-x+7=-6:3=-2\)
\(\Rightarrow-x=-2-7=-9\)
\(\Rightarrow x=9\)
Vậy x = 9
dễ mà
-12+3(-x + 7)=-18
3(-x +7)=-18 - (-12)
3(-x +7)=-30
(-x +7)=-30:3
(-x +7)=-10
-x =-10 -7
-x =-17
x =17
Vậy x=17
Nhớ k mik nha!!