Question

3) Qual é a soma dos ângulos internos de um pentágono regular?
a) S = 210
b) S = 540°
c) S = 150°
d) S = 60°

Answer 1

s=(n-2).180

s=(5-2).180

s= (3). 180

s= 540°

Answer 2

$\textsf{Letra B}$

Explicação passo a passo:

fórmula:

$\Large\boxed{\begin{array}{l} \Large\boxed{\begin{array}{l} \sf{S_i = (n - 2) \: . \: 180 {}^{ \circ} \rightarrow \begin{cases} \sf \: S_i = somar \,dos \,\hat{a}ngulos\, internos \\ \sf \: n =n\acute{u}mero\,de\, lados \end{cases}}\end{array}}\end{array}}$

Cálculos:

$\Large\boxed{\begin{array}{l} \Large\boxed{\begin{array}{l} \sf \:S_i = (n - 2) \: . \: 180 {}^{ \circ} \\ \\ \sf \:S_i = (5 - 2) \: . \: 180 {}^{ \circ} \\ \\ \sf \:S_i = 3 \: . \: 180 {}^{ \circ} \\ \\ \red{\boxed{ \boxed{ \sf{ \: \therefore \: S_i = 540 {}^{ \circ} \: }}}}\end{array}} \end{array}}$