Răspuns:
8,5 cm
Explicație pas cu pas:
[tex]\displaystyle{ R = \frac{abc}{4S} }[/tex]
[tex]\displaystyle{ ip^{2} = 8^{2} + 15^{2} = 64 + 225 = 289 }[/tex]
[tex]\displaystyle{ ip = \sqrt{289} = 17 \ cm}[/tex]
[tex]\displaystyle{ S = \frac{8 \cdot 15}{2} = 4 \cdot 15 = 60 \ cm^{2} }[/tex]
[tex]\displaystyle{ R = \frac{8 \cdot 15 \cdot 17}{4 \cdot 60} }[/tex]
[tex]\displaystyle{ R =\frac{2040}{240} = 8,5}[/tex]
