Respuesta :

Answer: 7

Step-by-step explanation:

To solve this problem you must apply the proccedure shown below:

1. You know that a multiplication has the following form:

a*b=c

Where a and b are the factors and c is the product.

2. You know one of the factor, then you can find the second one as following:

12*b=84

b=84/12

b=7

Therefore the answer is 7.