Aria ABCD = 49 cm²
Aria ABCD = l²
AB = BC = CD = AD
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l² = 49 => l = 7 cm
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Perimetrul lui ABCD = 4×l = 4×AB = 4×7 = 28 cm
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[tex]diagonala \: patratului \: are \: formula \: l \sqrt{2} [/tex]
BD, AC - diagonale
[tex]diagonala \: = 7 \sqrt{2} cm[/tex]
