Respuesta :

the answer is a=5 because you have to distribute the 3 so then it would be 3a-12+1=9-a then simplify that to 3a-11=9-a then it would be 4a-11=9 then it would be 4a=20 and then divided 4 by 20 and you get 5

Answer:

Step-by-step explanation:

-12a +1=9-13a- 9a....

i think a=5