Answer:
5 m
Step-by-step explanation:
The length of the side of a square is the root of the area of the square. The area of this square is the difference between the trapezoid area and the triangle area.
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square area = trapezoid area - triangle area
square area = 57.5 m² -32.5 m² = 25 m²
Then the side length is ...
side length = √(square area) = √(25 m²)
side length = 5 m
The length of a side of the square is 5 m.