Răspuns:
Raza cercului circumscris
[tex]R = \dfrac{2}{3} \cdot h = \dfrac{2}{3} \cdot \dfrac{\ell\sqrt{3} }{2} = \dfrac{9\sqrt{3} }{3} = 3\sqrt{3} \ cm[/tex]
Raza cercului înscris:
[tex]r = \dfrac{1}{3} \cdot h = \dfrac{1}{3} \cdot \dfrac{\ell\sqrt{3} }{2} = \dfrac{9\sqrt{3} }{6} = \dfrac{3\sqrt{3} }{2} \ cm[/tex]
Aria triunghiului:
[tex]A = \dfrac{\ell^2\sqrt{3} }{4} = \dfrac{9^2\sqrt{3} }{4} = \dfrac{81\sqrt{3} }{4} \ cm[/tex]
