
Answer:
 368 m
Step-by-step explanation:
The long side is opposite the 50° angle, and the short side is adjacent. Then the definition of the tangent ratio tells you ...
 Tan = Opposite/Adjacent
 tan(50°) = (100 m)/(short side)
Multiplying by (short side)/tan(50°) we get ...
 short side = 100 m/tan(50°) ≈ 83.9 m
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The perimeter of the field is the sum of side lengths: two times the short side plus two times the long side:
 P = 2(short side + long side) = 2(83.9 m +100 m) = 367.8 m
 P ≈ 368 m
The perimeter of the field is about 368 meters.