Question

How many sides does a regular polygon have if the measure of an exterior angle is 20

degree ?

(i) 20 (ii) 22 (iii) 18 (iv) 21​

Answer 1

Given:

• Side = 20

Find:

• Measure of each exterior angle of regular polygons.

Solution:

⟹ We know that the measure of exterior angle is (360/n)⁰ where n is the number of sides.

⟹ Here, it is given that the number of sides n=20, therefore,

⟹ (360/n)⁰ = (360/20)⁰ = 18⁰

❥ Hence, the measure of exterior angle is 18⁰. [Answer]

IᴛsPɪᴋᴀᴄʜᴜ_࿐

Answer 2

$\:\:\:\: \large \underline {\sf{Given\::}}$

➟ A regular polygon having exterior angle of measure 20°

$\:\:\:\: \large \underline {\sf{To\:Find\::}}$

➟ Number of sides this regular polygon have

$\:\:\:\: \large \underline {\sf{Solution\::}}$

• As we know that sum of exterior angle of a polygon is 360° .

• Therefore , to find the number of sides :

$\:\:\:\: \large {\boxed{\boxed{\sf{\pink{Number\:of\:sides\:=\: \dfrac{360 \degree}{ \theta}}}}}}$

➟ $\:\:\:\: \sf Number \:of\: sides\: = \: \cancel \dfrac{360}{20}$

➟ $\:\:\:\: \sf Number \:of \: sides \: = \: 18$

ᶠⁱⁿᵃˡ ᵃⁿˢ ⁱˢ 18 ˢⁱᵈᵉˢ

ᵃⁿᵈ ʷᵉ ᵃʳᵉ ᵈᵒⁿᵉ !

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