Answer:
Height of the building = 18.3 ft
Explanation:
Let the height of the building = x ft
From the picture attached,
A boy is standing on the building at a point A, car is at a point B and a bird is flying at C.
Applying Pythagoras theorem in ΔABD to find the distance AD.
AB² = BD² + AD²
AD =
![√(AB^2-BD^2)](https://img.qammunity.org/2021/formulas/mathematics/high-school/qd5d7ju2ednkfl4lqlpm35dfclw7s4gvj1.png)
=
![√(25^2-20^2)](https://img.qammunity.org/2021/formulas/mathematics/high-school/fm0vd74zrsusqzbad3tiheydsqa5g6j4fk.png)
=
![√(225)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/78d46sk5vye2ffupaii610r45ri2twturp.png)
= 15 units
Now from ΔACD,
tan(70)° =
![\frac{\text{CD}}{\text{AD}}](https://img.qammunity.org/2021/formulas/mathematics/high-school/wv5x74mf6tckqsqelcw9a3hti2vyn7ujuo.png)
1.22196 =
![(x)/(15)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/r2lpmluzjqwwu2p7iwl2zia2e3vpb0fl7k.png)
x = 15 × 1.22196
x = 18.33
≈ 18.3 ft
Therefore, height of the building is 18.3 ft.