Question

-12 ( x - 5 ) + 7 ( 3 - x ) = 5

- Tìm x

Answer 1

-12 ( x - 5 ) + 7 ( 3 - x ) = 5

​-60 - (-12x ) + 21 - 7x = 5

​-60 + 12x + 21 - 7x = 5

​( -60 + 21 ) + ( 12x - 7x ) = 5

​ -39 + 5x = 5

 

Answer 2

-12(x-5)+7(3-x)=5

-12x+60+21-7x=5

-12x-7x+(60+21)=5

-19x+81=5

-19x=5-81

-19x=-76

x=(-76):(-19)

x=4

Vậy x =4

Answer 3

-12( x - 5 ) + 7( 3 - x ) = 5

-12x + 12.5 + 7.3 - 7x = 5

( -12x - 7x ) + ( 60 + 21 ) = 5

-19x + 81 = 5

-19x         = 5 - 81

-19x         = -76

x             = (-76) : (-19)

x             =   4

vậy x=4