3.)$ABCDEF$ is a regular hexagon with area $1$. The intersection of $\triangle ACE$ and $\triangle BDF$ is a smaller hexagon. What is the area of the smaller hexagon?
For simplicity..I have constructed a hexagon with a side of 2
See...the image
![](/img/upload/7403616e005afb97f4a1933c/capture21.png)
A = (1, √3) and C = (1, - √3)
So...the distance from A to C = 2√3
And, by symmetry, GL is (1/3) of this = ( 2/3)√3
And this is one side of the smaller hexagon GHIJKL
So....the ratio of the area of the smaller hexagon to the larger hexagon =
(side of smaller hexagon)^2
______________________ =
(side of larger hexagon)^2
[ (2/3)√3]^2 (4/9) * 3 4 * 3 3 1
___________ = ______ = ______ = ____ = ____
2^2 4 4 * 9 9 3
So..in our case...the area of the smaller hexagon = (1/3) / 1 = 1/3 units^2
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