Question

An aeroplane us flying at a height of 210m flying at this height at some instant the angle of depression of two points in a line in opposite directions on both the banks of the river are 45°and 60°.find the width if the river ( use √3=1.73)

Answer 1

hope this help u.....

Answer 2

let the horizontal distance between aeroplane to nearest point is x m

tan 45= 210/X

1=210/X

X=210 m

let the horizontal distance between aeroplane to the farthest point is Y m

tan 60 = 210/Y

√3=210/Y

Y=210/√3

Y=121.25 m

So the width of river= X+Y m

210+121.25

331.25m