Answer:
[tex]12\sqrt{2}\ cm[/tex]
Step-by-step explanation:
step 1
Find the length side of the square
we know that
The area of a square is equal to
[tex]A=b^{2}[/tex]
where
b is the length side
we have
[tex]A=144\ cm^2[/tex]
substitute in the formula of area
[tex]144=b^{2}[/tex]
solve for b
square root both sides
[tex]b=12\ cm[/tex]
step 2
Find the length of the diagonal
Applying the Pythagorean Theorem
[tex]d^2=b^2+b^2[/tex]
see the attached figure to better understand the problem
substitute the given values
[tex]d^2=12^2+12^2[/tex]
[tex]d^2=288[/tex]
square root both sides
[tex]d=\sqrt{288}\ cm[/tex]
simplify
[tex]d=12\sqrt{2}\ cm[/tex]