Answer:
Step-by-step explanation:
Use Pythagorean theorem to find the length of the square.
Length of the square = a
a² +a² = diagonal²
2a² = 12²
2a² = 144
a² = 144 ÷ 2
a² = 72
[tex]a =\sqrt{72}\\\\ = \sqrt{2*2*2*3*3}\\\\ = 2*3\sqrt{2}\\\\a = 6\sqrt{2}\\\\\\\\Perimeter= 4a\\\\ = 4*6\sqrt{2}\\\\= 24\sqrt{2} cm[/tex]
