Answer: x ≈ 18 ft
Step-by-step explanation:
We will use our trig knowledge to solve this.
The man is standing 10 ft away, but we also need to add the 5 ft shadow as well as that is a point on our triangle.
We can set up a simple trig equation of: tan(50) = x/15
x being the height of the lamppost.
Now we solve.
tan(50) = 1.1918
1.1918 *15 = x
x = 17.876
Now round to the nearest foot.
x ≈ 18 ft