Answer;
[tex]\begin{gathered} \text{formula; A(x) = x}^2 \\ \text{for 3cm ; A = 9 cm}^2 \\ \text{for 10.5 cm; A = 110.25 cm}^2 \\ \text{for 3.14 cm; A = 9.8596 cm}^2 \end{gathered}[/tex]Expanations;
Mathematically, the area of a square is the product its side lengths. Since a square has all its side equal, then the area is the square of the side length
So, for a square with side x cm, we have the formula for the area as;
[tex]A(x)=x^2[/tex]So, to get the areas with the given side lengths, we have the following;
[tex]\begin{gathered} 1)A(3)=3^2=9cm^2 \\ 2)A(10.5)=10.5^2=110.25cm^2 \\ 3)A(3.14)=3.14^2=9.8596cm^2 \end{gathered}[/tex]