A^2+b^2=c^2
5^2+b^2=12^2
25+b^2=144
b^2=144-25
b^2=119
SQUARE ROOT BOTH SIDES:
b=10.9
The answer is c.
<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
</span>
90 + 50 = 140
140 - 7 = 133
130 - 140
