Answer:12.59
Step-by-step explanation:
enter image source here
From the diagram you can see that we have constructed a right triangle, with height A and base 15.
Length of shadow = 15 feet.
Height of flagpole = A.
We know the angle of elevation is
40
∘
. Using this angle and the tangent ratio, we can find A.
tan
(
40
∘
)
=
opposite
adjacent
=
A
15
∴
tan
(
40
∘
)
=
A
15
Rearranging:
A
=
15
tan
(
40
∘
)
By calculator:
A
=
12.59
feet. ( 2 d.p.)
