Question

quantos diagonais tem um polígono de 23 lados?

Answer 1

Sendo n o n° de lados;
e d as diagonais;

$d= \frac{n(n-3)}{2} \to \\\\d= \frac{23(23-3)}{2} \to\\\\ d= \frac{23*20}{2} \to\\\\ d= \frac{460}{2} \to \\\\ d=230diagonais$