Respuesta :

I think 9 should be added to both sides.

cofficient of x = 6

half of it = 6/2 = 3

square the 3

to give 3 squared = 3*3 9

Answer:

9

Step-by-step explanation:

To make it a Perfect Square Trinomial, you can square root 9 and multiply it to get 6, therefore 9 is correct