AB=AC=10 cm
AD=8 cm
- Aplicam Pitagora in ΔADB dr in D
AB²=AD²+BD²
100=64+BD²
BD=√36
BD=6 cm⇒ BC=12 cm
P=AB+AC+BC=10+10+12=32 cm
Teorema sinusului:
[tex]\frac{b}{sinB}=2R\\\\ \frac{AC}{sinB} =2R\\\\\frac{10}{\frac{AD}{AB} }=2R\\\\ \frac{10}{\frac{8}{10} } =2R\\\\100=16R\\R=6,25 cm[/tex]
sau
[tex]A=\frac{abc}{4R} \\\\A=\frac{AD\times BC}{2} =\frac{8\times 12}{2} =48cm^2\\\\48=\frac{10\times10\times12}{4R} \\\\\\R=6,25cm[/tex]
