Respuesta :

8x-4x+6-12=25+3x
x=31
I think this is right hope it helps 
8 x - 4 x + 6 - 12 = 25 + 3 x

8 x - 4 x - 3 x = 25 - 6 + 12

4 x - 3 x = 19+12

x = 31

hope this helps!