Answer:
18 ft
Step-by-step explanation:
Given that:
Length of ladder = 15 ft
Distance of ladder's foot from the building = 9 ft
Height of flagpole erected on the roof = 6 ft
To find:
Height of the top of flagpole from the base of the building?
Solution:
The given situation can be represented from the figure as attached in the answer area.
We have to find the length of [tex]BD[/tex].
There is a right angle [tex]\triangle ABC[/tex], right angled at point [tex]B\\[/tex].
We can use Pythagorean theorem here to find the side [tex]BA[/tex].
As per Pythagorean theorem:
[tex]\text{Hypotenuse}^{2} = \text{Base}^{2} + \text{Perpendicular}^{2}\\\Rightarrow AC^{2} = BC^{2} + AB^{2}\\\Rightarrow 15^2 = 9^2+AB^2\\\Rightarrow AB^2 = 225-81\\\Rightarrow AB = \sqrt {144}\\\Rightarrow AB =12\ ft[/tex]
[tex]BD = BA + AD\\\Rightarrow BD = 12 + 6\\\Rightarrow BD = \bold{18\ ft}[/tex]