Question

A man 6 feet tall begins walking away from a light pole that is 15ft tall at a rate of 5ft/s. How fast is the tip of his shadow moving when he is 40 feet away from the pole?

Answer 1

\[\ \frac{ d }{ dt }(x+y) and \frac{ dx }{ dt }=5ft/\sec\]

Answer 2

my book is telling me "by similiar triangles", 15/6 = (x+y)/y

Answer 3

what does that mean?>

Answer 4

basically it's saying that

Answer 5

which means the you can make a proportional ratio with same sides

Answer 6

why is it x+y/y