Please help me.

Question

At 10 PM a 5 foot 6 inch tall young lady is directly below a street lamp which is on a pole 25 feet in the air. This young lady begins walking in a straight line away from the street light at 6 feet per second. After how many seconds is the shadow she cast 11 feet long?

Answer 1

Set up the ratio:

 

5.5/11 = 12/(11+x)  and solve for x

 

132 = 5.5x + 60.5

 

x = 13 ft

 

Answer 2

 |

 |

 |

 |            | 

 |_______|_________

    6t             11

 

So yeah, it's hard to draw here. The higher vertical line is 25 feet, and the other vertical line is 5.5 feet (6 in = .5 ft)

 

Just draw the hypotenuse and make sure it touches both heights so that you could have similar triangles.

 

So by similar triangle, that will be:

 

(6t+11)/25 = 11/5.5

 

t = 6.5 seconds