Answer:
B. 4
Explanation:
Let the side of the square= a
Then the area of the square= a²
Given:
Then:
Considering the value of the area, 12 units
- x²-4 =12
- x²=16
- x= √16
- x= ±4
- x= -4 is not considered as the length can't be negative
- x= 4 is the answer
Correct choice is B. 4