Question

quantas diagonais tem o undecagono?

Answer 1

11.(11-3)/2 = 11.8/2 = 88/2 = 44 diagonais

Answer 2

Após resolver os cálculos, concluímos que um Undecágono tem:

$\Large\displaystyle\text{ \begin{gathered} \hookrightarrow\boxed{\boxed{\bf 44~ diagonais}}\end{gathered} }$

Para calcular o número de diagonais de um polígono usamos a fórmula:

$\Large\displaystyle\text{ \begin{gathered} \sf{ d = \dfrac{n \cdot(n - 3)}{2} } \end{gathered} }$

Onde:

$\Large\displaystyle\text{ \begin{gathered} \sf{ \begin{cases} \sf d = diagonais \\ \sf n =n\acute{u}mero\, de\, lados \end{cases} } \end{gathered} }$

Substituindo n por 11 na fórmula obtemos:

$\Large\displaystyle\text{ \begin{gathered} \sf{ d = \dfrac{n \cdot(n - 3)}{2} } \end{gathered} }$

$\Large\displaystyle\text{ \begin{gathered} \sf{ d = \dfrac{11 \cdot(11 - 3)}{2} } \end{gathered} }$

$\Large\displaystyle\text{ \begin{gathered} \sf{ d = \dfrac{11 \cdot8}{2} } \end{gathered} }$

$\Large\displaystyle\text{ \begin{gathered} \sf{ d = \dfrac{88}{2} } \end{gathered} }$

$\Large\displaystyle\begin{gathered} \sf{ d = 44 } \end{gathered}$