Explicație pas cu pas:
AO = BC = CO = 2 u.m.
BC = 4 u.m.
[tex]AB = AC = \sqrt{ {2}^{2} + {2}^{2} } = \sqrt{8} = 2 \sqrt{2} \: u.m. \\ [/tex]
[tex]P_{\triangle ABC} = AB + AC + BC = \\ = 2 \sqrt{2} + 2 \sqrt{2} + 4 = 4 \sqrt{2} + 4 = \bf 4( \sqrt{2} + 1) \: u.m. \\ [/tex]
[tex]Aria_{\triangle ABC} = \frac{AO \cdot BC}{2} = \frac{2\cdot2}{2} = \frac{4}{2} = \bf 2 \: {u.m.}^{2} \\ [/tex]
