Question

tìm x thuôc z

12-x+2.( 7-x) =29

Answer 1

12-x+2.(7-x)=29

12-x+(14- 2x)=29

12-x+14-2x=29

26-3x=29

3x=26-29

3x=-3

x=-3:3

x=-1

Vậy x=-1

Answer 2

12 -x + 2(7 - x) = 29

12 - x + (14 - 2x) = 29

12 - x + 14 - 2x = 29

26 - 3x = 29

3x = 26 - 29

3x = -3

=> x = -1