Question

an adult an a minor boys standing on the ground are two meters apart. The height of the adult is 4 times the height of minor boy..If at the mid point of the line segment joining their feet the angles of elevation of their tops are complementary then find the height of the minor boy..

Answer 1

Hi,

Draw a rough diagram according to

the problem given,

A |
|
| E l
l l
I Dl
--------------C------------
B 1 1

Join A and E to D ,

Let the height of the minor boy = DE = h m

the height of the Adult = AB = 4h m

Distance between them = BC = 2m

BC = CD = 1 m

i ) In triangle ABC ,

Angle ACB = x

< ABC = 90

Tan x = AB / BC

Tan x = 4h /1 ---------( 1 )

ii ) in triangle ECD,

Angle ECD = 90 - x ( since completary angles )

< EDC = 90

Tan ( 90 - x ) = ED / CD

Cot x = h / 1 ------( 2 )

Multiply ( 1 ) and ( 2 ), we get,

Tan x Cot x = 4h × h

1 = 4h^2

1/4 = h^2

h^2 = 1/4

h = 1/2 m

Therefore,

Height of the boy = h = 1/2 = 0.5 m

Height of the adult = 4h = 4 × 0,5 = 2 m

I hope this helps you.

:)

Answer 2

Step-by-step explanation:

this is your answer of your questions 2 km split into 1m and 1 m