- #1
Swerting
- 35
- 0
Homework Statement
A rectangle has a constant area of 200m2 and its length L is increasing at the rate of 4 meters per second. Find the width W at the instant the width is decreasing at the rate of 0.5 meters per second.
Homework Equations
[tex]A=200[/tex]
[tex]dA/dt =0[/tex] (since the area is constant)
[tex]dL/dt =4 m/s[/tex]
[tex]dW/dt =-0.5 m/s[/tex]
[tex]A=(L)(W)[/tex]
and I'm not sure, but parameter is [tex]P=2L+2W[/tex]
The Attempt at a Solution
I wrote L in terms of W, and W in terms of L, but I am having trouble taking L=(200/W) to dL/dt.
I know that most related rates problems need two equations, so I have been trying to figure out how parameters may work in. Any help is greatly appreciated.
Last edited: