A street light is at the top of a 19 ft tall pole. A woman 6 ft tall walks away from the pole with a speed of 5 ft/sec along a straight path. How fast is the tip of her shadow moving when she is 40 ft from the base of the pole?
Rate =

Question

A street light is at the top of a 19 ft tall pole. A woman 6 ft tall walks away from the pole with a speed of 5 ft/sec along a straight path. How fast is the tip of her shadow moving when she is 40 ft from the base of the pole? 
Rate =

myininaya · Answer

did you try drawing a traingle.  You have a triangle inside a triangle.  So you should set up the equation (x+y)/19=y/6
then you get y=6x/13
y'=6x'/13
but remember you are looking for x'+y'

myininaya · Answer

does this help?

anonymous · Answer

yeah...... but what's the final answer.

myininaya · Answer

i got 5ft/s+30/13 ft/s

myininaya · Answer

[13(5)+30]/13 ft/s=[45+30]/13ft/s=75/13 ft/s