A reflection over the x axis coupled with another reflection over the y axis leads to a rotation of 180 degrees.
In other words,
Start with point A. Reflect over the x axis to get point B. Reflect B over the y axis to get point C. To go from A to C, we can rotate A 180 degrees about the origin.
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So this means that if we do those reflections and then do the rotation, then we end up back where we started. Wherever point A is located, the point A' will also be located at the same position with the same coordinates.
So u have to add all the sides up. which will give you 6 + 6√3 + 6 +6√3 because their opposite and parallel lengths and widths are equal that gives you 12 + 12√3 so ans is 12m + 12√3m