Answer:
18.4 cm
Step-by-step explanation:
A square has equal sides. Let's say one side is x. The area would be x^2. We know the area to be 169 cm^2, so:
x^2 = 169 cm^2
x = 13 cm
The diagonal, z, would form a right triangle with two sides of length 13 cm. The Pythagorean theorem can be used:
13^2 + 13^2 = z^2
z^2 = 338
z = 18.38 cm, or 18.4 cm
