Question

Quantas diagonais possui o icosagono de 20 lados

Answer 1

sao 170 diagonais
espero ter ajudado

Answer 2

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

$\Large \text{ \sf{ d = \dfrac{20 \cdot(20 - 3)}{2} } }$

$\Large \text{ \sf{ d = \dfrac{20 \cdot17}{2} } }$

$\Large \text{ \sf{ d = \dfrac{340}{2} } }$

$\Large \text{ \boxed{ \boxed{\sf{ d = 170}}} }$