Calculate the length of the side of the square to 1dp.

Answer:
72 cm
Step-by-step explanation:
You can solve this problem using the properties of the 45-45-90 right triangle. Assuming the 12 cm is a diagonal of the square, each side of the square can be modeled as x, and the diagonal will be x[tex]\sqrt{2}[/tex].
This means [tex]x\sqrt{2} =12[/tex], so [tex]x=\frac{12}{\sqrt{2} }[/tex].
Next, to find the area of the square you take the square of any of its sides. Since x is the length of one side, and [tex]x=\frac{12}{\sqrt{2} }[/tex] , you can square [tex]\frac{12}{\sqrt{2} }[/tex] to get the area. This is equal to [tex]\frac{144}{2}[/tex] or 72 cm.