Hello, kycon90!

Did you make a sketch?

A streetlight is at the top of a 14 ft tall pole.

A woman 6 ft tall walks away from the pole with a speed of 5 ft/sec.

How fast is the tip of her shadow moving when she is 30 ft from the base of the pole? Code:

A o
| * - C
| o
| | *
14| | *
| 6| *
| | *
| | *
B o-------o-----------------------o E
: - x - D - - - s-x - - - - - :
: - - - - - - s - - - - - - - - :

The lightpole is:

The woman is:

Her distance from the pole is:

The tip of her shadow is ft from the pole: .

. . Hence: .

Since , we have: .

Differentiate with respect to time: .

Therefore: .