Question

in triunghiul abc avem ab=7 bc=8 ac=9 aflati raza cercului inscris in triunghi

rpd va roooog

Answer 1

Răspuns:

Explicație pas cu pas:

Answer 2

$\it p=\dfrac{\mathcal{P}}{2}=\dfrac{7+8+9}{2}=12\\ \\ \\ \mathcal{A}=\sqrt{p(p-a)(p-b)(p-c)}=\sqrt{12\cdot4\cdot3\cdot5}=\sqrt{12^2\cdot5}=12\sqrt5\ \ \ \ \ (1)\\ \\ \mathcal{A}=p\cdot r=12r\ \ \ \ \ (2)\\ \\ (1),\ (2) \Rightarrow 12r=12\sqrt5|_{:12} \Rightarrow r=\sqrt5$