Answer:
3115.03301179982 metersThis value is approximate
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Refer to the image attachment
Segments
AB = 1100 meters = height of blimp
DE = x meters = distance between stadiums
AD = y meters
AE = AD+DE = y+x
Angles
Angle ADB = angle CBD = 75.2 degrees
Angle CBE = angle BEA = 17.9 degrees
Focus on triangle ADB
tan(angle) = opposite/adjacent
tan(D) = AB/AD
tan(75.2) = 1100/y
y*tan(75.2) = 1100
y = 1100/tan(75.2)
y = 290.632536450073
Focus on triangle AEB
tan(angle) = opposite/adjacent
tan(E) = AB/AE
tan(E) = 1100/(y+x)
tan(17.9) = 1100/(290.632536450073+x)
0.32299119934583 = 1100/(290.632536450073+x)
0.32299119934583(290.632536450073+x) = 1100
93.8717515169298+0.32299119934583x = 1100
0.32299119934583x = 1100-93.8717515169298
0.32299119934583x = 1006.12824848308
x = 1006.12824848308/0.32299119934583
x = 3115.03301179982This answer is approximate