Judging from the meaning of the question: ABC = 90,
BC=AB=x meters, BD=(x+60) meters.
In Rt△ABD,
tan∠ADB=ABBD=xx+60=33
∴3x=3x+603
X = 30 (1+3) = 8 1.96 (m)
A: The width of the river is about 8 1.96 meters.