Mathematics

Problem

A rectangle has constant area

100\text{ cm}^2

. The width

w

of the rectangle is increasing at a rate of

2\text{ cm/s}

. What is the instantaneous rate of change of the length

\ell

when the width is

5\text{ cm}

? a)

8\text{ cm/s}

-0.5\text{ cm/s}

-8\text{ cm/s}

-4\text{ cm/s}