10 units
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Use formula for the area of a regular hexagon.
where, s - is side and a - is the apothem
There is relationship between the length of the side and the apothem that is specific to regular hexagons:
We can use this relationship to eliminate s in the area formula, giving us:
The area of the hexagon is given, we equate the values to find the apothem:
After cancelling the
from both sides, we simplify the formula to:
So the apothem is 10 units.