Mathematics

Problem

The length of a rectangle is increasing at

3\,\text{cm/s}

while its width is decreasing at

3\,\text{cm/s}

. What is the instantaneous rate of change of its perimeter? a)

12\,\text{cm/s}

0\,\text{cm/s}

6\,\text{cm/s}

-6\,\text{cm/s}