Respuesta :

Answer:

x = -1

Step-by-step explanation:

-3 +12 = 9

-9x = 9

-9(-1)=9

9 - 12 = -3

-9x-12=-3
Multiply by -1
9x+12=3
Divide by 3
3x+4=1
Subtract 4
3x=-3
Divide by 3
x=-1