Question

the length of a rectangle is increasing as a rate of 8cm/s and the width at 3cm/s. when the length is 20cm and the width is 10cm, how fast is the are of the rectangle increasing?

Answer 1

When the length is 20cm, the width is 10 cm and the area is 200 square cm
When the length is 28cm, the width is 13cm and the area is 364 square cm
The speed is increasing at the rate of 164 square cm.