Problems from The square

Imagine a square that measures $$13cm$$ on one side. Calculate the perimeter, area and diagonal.

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The perimeter is the sum of the sides. In the case of a square, all four sides are equal: $$$P=4\cdot13=52 \ cm$$$

The area of the square is: $$$A=13^2=169 \ cm^2$$$

And finally, to calculate the diagonal, we use Pythagoras' theorem: $$$d=\sqrt{l^2+l^2}=\sqrt{2l^2}=\sqrt{2}\cdot l=\sqrt{2}\cdot13=18,4 \ cm$$$


$$P=52 \ cm$$

$$A=169 \ cm^2$$

$$d=18,4 \ cm$$

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