Question

1. Diagonala unui pătrat are lungimea 14 cm. Determinaţi perimetrul pătratului.
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Answer 1

$d_{\square} = \ell \cdot\sqrt{2} \iff 14 = \ell \cdot\sqrt{2}$

$\ell = \dfrac{14}{\sqrt{2} } \implies \ell = 7\sqrt{2}$

$P_{\square} = 4 \cdot \ell = 4 \cdot 7\sqrt{2} \implies P_{\square} = 28\sqrt{2} \ cm^{2}$