Answer:
Well I answered in the comments, but I need points so the answers are (in order) 12, 2, and 144
Explanation:
Since it's a square, the sides will be the same length. If the perimeter is 48, then you divide 48 by 4 and you will have 12- your answer.
For x, subtract 2 from 12 to get ten, then divide that by five to get your answer which would be 2.
If the side length is 12, you square that and 12 squared is 144.