Answer:
The perimeter of the base of the birdhouse is 36 units
Step-by-step explanation:
<u><em>The complete question is</em></u>
Chase is building a birdhouse in the shape of a regular polygon. He knows that the measure of the interior angle is twice the measure of the exterior angle and the length of a diagonal that passes through the center is 12. What is the perimeter of the base of the birdhouse?
step 1
Find the measure of the interior angle
Let
x ---> the measure of the interior angle
y ---> the measure of the exterior angle
Remember that
the sum of the interior and exterior angle in any polygon is equal to 180 degrees
so
----> equation A
we have that
the measure of the interior angle is twice the measure of the exterior angle
so
----> equation B
substitute equation B in equation A
![2y+y=180](https://tex.z-dn.net/?f=2y%2By%3D180)
![y=60^o](https://tex.z-dn.net/?f=y%3D60%5Eo)
so
![x=120^o](https://tex.z-dn.net/?f=x%3D120%5Eo)
That means-----> The figure is a regular hexagon
step 2
Remember that
The length of the diagonal that passes through the center of the hexagon is equal to two times the length of the regular hexagon
Let
b ----> the length side of the hexagon
so
![b=12/2=6\ units](https://tex.z-dn.net/?f=b%3D12%2F2%3D6%5C%20units)
The perimeter of the hexagon is given by the formula
![P=6b](https://tex.z-dn.net/?f=P%3D6b)
substitute
![P=6(6)=36\ units](https://tex.z-dn.net/?f=P%3D6%286%29%3D36%5C%20units)