Answer: 21.21 cm
Step-by-step explanation:
Given
length of diagonal on the square is 30 cm
Suppose a is the side length of the square
and length of diagonal is given as [tex]a\sqrt{2}\ units[/tex]
So,
[tex]\Rightarrow a\sqrt{2}=30\\\\\Rightarrow a=\frac{30}{\sqrt{2}}=21.21\ cm[/tex]
Thus, the side length of the square is 21.21 cm