Aspotlight on the ground shines on a wall 12 m away. if a man 2 m tall walks from the spotlight toward the building at a speed of 1.9 m/s, how fast is the length of his shadow on the building decreasing when he is 4 m from the building?

v = 2.85 m/s

Explanation:

By the law of similarity of the triangle we can say

here we know that

height of man = 2 m

let the distance of man from spotlight = x

distance of wall from spotlight = 12 m

height of image is let say "y"

so we will have

now we have

here we know

x = 4 m

now we have

false br

its c i just checked it