Question

Calcule a medida do ângulo interno do polígono regular ICOSÁGONO (tem 20 lados): *
O a) 72°
O b) 1440
O c) 90°
O d) 1440°​

Answer 1

Resposta:

Ae: ângulo externo

Ai: ângulo interno

Ae=360/n=360/20 =18°

Ai+Ae=180°

Ai =180-18 =162°

Answer 2

$\large\displaystyle\boxed{ \begin{array}{l} \sf \: A_i = \dfrac{(n - 2) \cdot180 {}^{ \circ} }{n} \\ \\ \sf \:A_i = \dfrac{(20 - 2) \cdot180 {}^{ \circ} }{20} \\ \\ \sf \: A_i = \dfrac{18 \cdot180 {}^{ \circ} }{20} \\ \\ \sf \:A_i = \dfrac{3240 {}^{ \circ} }{20} \\ \\ \boxed{ \boxed{ \sf{A_i = 162 {}^{ \circ} }}} \end{array}}$