Question

Tìm x thuộc n:12.x+13.x=390

Answer 1

12x + 13x = 390

=> x(12 + 13) = 390

=> 25x = 390

=> x = 390 : 25

=> x = 15,6

vậy_

Answer 2

12x + 13x = 390 

=> 25x = 390 

=> x = 390  : 25 

=> x = \(\frac{78}{5}\)

Vậy x = \(\frac{78}{5}\)