calculati aria unui patrat cu diagonala de 8 cm

Răspuns :

Răspuns

A = l²

sau

A = d² / 2

A = 8² / 2 = 64/2 = 32 cm²

[tex]Diagonala\ este\ =\ l\sqrt{2}  \rightarrow l=\frac{diagonala}{\sqrt{2} } \\\\l=\frac{8}{\sqrt{2}}=  \frac{8\sqrt{2}}{2}=4 \sqrt{2}  \\\\Aria=l^{2} =(4\sqrt{2})^{2}=16x2=32\ cm[/tex]