Question

calcule a soma das medidas dos nagulos internos de um dodecágono

Answer 1

Si = 180 * (n-2)
Si = 180 * (12-2)
Si = 180 * 10
Si = 1800º

Answer 2

$\large\boxed{\begin{array}{l} \sf \:S_i = (n - 2) \: . \: 180 {}^{ \circ} \\ \\ \sf \:S_i = (12 - 2) \: . \: 180 {}^{ \circ} \\ \\ \sf \: S_i = 10 \: . \: 180 {}^{ \circ} \\ \\ \boxed{ \boxed{ \sf{S_i = 1800 {}^{ \circ} }}}\end{array}}$