Question

Quantas diagonais tem um heptágono?

Answer 1

d = n.(n-3)/2

d = 7.(7-3)/2

d = 7.(4)/2

d= 28/2

d = 14 ✓

Answer 2

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

$d = \dfrac{7 \cdot(7 - 3)}{2}$

$d = \dfrac{7 \cdot4}{2}$

$d = \dfrac{28}{2}$

$d = 14$