9,10,12,x,20,25; the median is 14.

Step-by-step explanation:

In statistics, the median is a central measure, which represents the value placed in the middle.

In this case, the middle value is between 12 and x. To find the median, we have to find the mean between those two values

But, we know by given that the median is 14, we replace it and solve for

Therefore, the unknown value is 14.

2 is the final ! : )