Tuesday

January 27, 2015

January 27, 2015

Posted by **Katie** on Sunday, February 6, 2011 at 4:59pm.

I think the answer is 55 mph because I added 60 + 55 and divided by 2 and got 55 mph.

- Calculus -
**Damon**, Sunday, February 6, 2011 at 5:09pmOh my :(

The distance between them is the hypotenuse of a right triangle.

D^2 = x^2 + y^2

where

x = 50 t

y = 60 t

so

D^2 = 2500 t^2 + 3600 t^2 = 6100 t^2

now take time derivative

2 D dD/dt = 12200 t

at t = 1.5

D^2 = 6100 (2.25)

D = 117 miles

2 D = 234.3 miles

so

dD/dt = 12200(1.5)/234.3 = 78.1 miles/hour

**Answer this Question**

**Related Questions**

calculus - Two cars start from the same point at the same time. One travels ...

Maths - Two cyclists depart from the same point. One travels due East at 18km/hr...

calculas maths - .Two hikers begin at the same location and walk in ...

math - Two trucks left buck's trucks traveling in opposite directions. One truck...

math - A man travels 4km due north,then travels 6km due east and further travels...

Physics - A truck travels due east for a distance of 1.7 km, turns around and ...

math - Can you check my answer to see if i really get this word problem thing A ...

calculus - Two cars start moving from the same point. One travels south at 28mi/...

Physics - Two bicyclists, starting at the same place, are riding toward the same...

Calculus - Two automobiles start from a point A at the same time. One travels ...