Page 30 - DIGITAL BOOK MUHAMMAD AZWARDI NASUTION

EXAMPLE:

A pentagon has side which form

arithmetic sequence. If the smallest angle

is 66 then find the biggest angle.
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Answer:

The sum of angles pentagon is 540 .
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Suppose that the angles are

a-2b , a-b , a , a + b , a+2b

So 5a=540 o

a= 108 o

a – 2b = 66 o

108o – 2b = 66 o

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2b = 108 – 66 o

2b = 42 o

The biggest angle is 108 + 42 = 150 o
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