<span><u>Answer </u>
A) 〖128.6〗^o
<u>Explanation </u>
The question requires us to find the interior angle of a regular heptagon.
To do this first calculate the exterior angle of that polygon.
The sum of exterior angles is 360o. A heptagon has 7 sides.
So, one exterior angle = 〖360〗^o/7=〖51.4〗^o
interior angle+exterior angle=〖180〗^o
exterior=180-51.4=〖128.6〗^o
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I know the B is 2
Sorry I don't know the A
The measure of angle x will be 88 degrees. Then the correct option is C.
The complete question is attached below.
<h3>What is law of cosine?</h3>
Let there is a triangle ABC such that |AB| = a units, |AC| = b units, and |BC| = c units and the internal angle A is of θ degrees, then we have:
2ab cos θ = a² + b² – c²
The triangle is shown below.
Then the value of the variable x will be
2 · 7 · 10 · cos x = 7² + 10² – 12²
140 · cos x = 49 + 100 – 144
cos x = (149 – 144) / 140
x = 87.95 ≈ 88°
Then the correct option is C.
Learn more about law of cosines here:
brainly.com/question/17289163
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20
Formula for perimeter: length x 2 + width x 2
70x2 is 140 then subtract it from 180 and you’ll get 40, then you half it and get 20
A atomic number
B atomic symbol
C atomic name
D atomic mass