Tuesday

September 23, 2014

September 23, 2014

Posted by **sara** on Tuesday, October 16, 2012 at 2:53am.

- calculus -
**Reiny**, Tuesday, October 16, 2012 at 9:18amsame question ....

http://www.jiskha.com/display.cgi?id=1333489636

just change the necessary numbers

- calculus -
**Steve**, Tuesday, October 16, 2012 at 11:04amsince you have a calculus class, you probably ought to do it Reiny's way, but sometimes a little simplification can save you some work:

If the man is x away from pole, ad his shadow length is s, then using similar triangles,

s/2 = (x+s)/6

s = 1/2 x

so, ds/dt = 1/2 dx/dt

since the tip of the shadow is x+s from the pole, it is moving at

dx/dt + ds/dt = dx/dt + 1/2 dx/dt = 3/2 dx/dt = 3/2(1.4) = 2.1 m/s

**Answer this Question**

**Related Questions**

calculus - A street light is mounted at the top of a 15-ft-tall pole. A man 6 ft...

Math - A street light is mounted at the top of a 15-ft-tall pole. A man 6 ft ...

math - A street light is mounted at the top of a 19-ft-tall pole. A man 5.5 feet...

Calculus - A street light is at the top of a 17 ft tall pole. A woman 6 ft tall ...

calculus - A street light is at the top of a 13 ft tall pole. A woman 6 ft tall ...

calculus - A street light is at the top of a 20 ft tall pole. A woman 6 ft tall ...

calculus - A street light is at the top of a 16 ft tall pole. A woman 6 ft tall...

calculus - A street light is at the top of a 15 ft tall pole. A woman 6 ft tall ...

calculus - A street light is at the top of a 16 ft tall pole. A woman 6 ft tall...

Calculus 1 - A street light is at the top of a 19 ft tall pole. A woman 6 ft ...