If the side length of a diamond is 2, then the square sum of the two diagonals of the diamond is 2______ .

If the side length of a diamond is 2, then the square sum of the two diagonals of the diamond is 2______ .

Let the length of two diagonals be a and B respectively, then (12a) 2 + (12b) 2 = 22, so A2 + B2 = 16