An aeroplane is flying at a height of 300 m above the ground
An aeroplane is flying at a height of 300 m above the ground. Flying at this height, the angles of depression from the aeroplane of two points on both banks of a river in opposite directions are 45° and 60° respectively. Find the width of the river. [Use √3 = 1.732]
Solution
tan 45° = 300/y
1 = 300/y
y = 300
tan 60° = 300/x
√3 = 300/x
x = 300/√3
x = 100√3
Width of river = x + y
= 300 + 100√3
= 300 + 173.2
= 473.2 m