Question

tìm x biết : 2x-5=(x-7)+(12-5x)

Answer 1

2x-5=(x-7)+(12-5x)

2x-5=x-7+12-5x

=>2x-x+5x=-7+5+12

      x+5x=-2+12

      6x    =10

=>x=10:6

   x=10/6=5/3

Vậy x=5/3

Hok tốt

Answer 2

\( 2x - 5 = \left( {x - 7} \right) + \left( {12 - 5x} \right)\\ \Leftrightarrow 2x - 5 = x - 7 + 12 - 5x\\ \Leftrightarrow 2x - 5 = - 4x + 5\\ \Leftrightarrow 2x + 4x = 5 + 5\\ \Leftrightarrow 6x = 10\\ \Leftrightarrow x = \dfrac{{10}}{6} \)

Answer 3

       Trả lời:

2x - 5 =( x - 7) + ( 12 - 5x )

2x - 5 = x  - 7  +    12 - 5x

=> 2x - x + 5x = - 7 + 5 + 12

     x + 5x = -2 + 12

     6x      = 10

=> x        = 10 : 6

     x        = 3/5

              # Kiều