Question

quantos  lados tem um poligono cujo o número de diagonais é 3  do número de lados?                                                                                                       2

                                                                                                                   

                                                                                                                   

Answer 1

n = nº de lados

$<var>d=\frac{3n}{2}\\ d=\frac{n*(n-3)}{2}\\ \frac{3n}{2}=\frac{n*(n-3)}{2}\\ 3n=n^2-3n\\ n^2-6n=0 \\n-6=0 \\n=6</var>$