Respuesta :

Answer: 9

Step-by-step explanation:

If 12 is the whole length, and 3 is a small section of it, then 3 + j = 12

Or 12 - 3 = j

Therefore, 12 - 3 = 9

Answer:

9 = j

Step-by-step explanation:

12 - j = 3

Adding j to both sides, we get 12 = 3 + j

Combining like terms, we get 9 = j