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Here is a pentagon work out the value y.

Here is a pentagon work out the value y.-example-1
User Yaakov
by
7.0k points

2 Answers

0 votes

Answer:

125°

Explanation:

First you find the value of total interior angles

Since it's a Pentagon


(5- 2) * 180

Then you arrive at 540°

When you sum all the angles in the Pentagon together they should be equal to 540


540 = 86 + 142 + 72 + 115 + y


540 = 415 + y


540 - 415 = y


y = 125

User Ekos
by
6.5k points
3 votes

Answer:

y = 125°

Explanation:

the sum of the interior angles of a polygon is

sum = 180° (n - 2) ← n is the number of sides

here n = 5 , then

sum = 180° × (5 - 2) = 180° × 3 = 540°

sum the interior angles and equate to 540°

y + 86° + 142° + 72° + 115° = 540°

y + 415° = 540° ( subtract 415° from both sides )

y = 125°

User Sharjeel Aziz
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7.2k points