Question -
Answer -
Since the length (x)┬аis decreasing at the rateof 5 cm/minute and the width (y)┬аisincreasing at the rate of 4 cm/minute, we have:
and┬а
(a) The perimeter (P)┬аof a rectangle is givenby,
P┬а= 2(x + y)
Hence, the perimeter is decreasing at the rate of 2cm/min.
(b) The area (A)┬аofa rectangle is given by,
A┬а=┬аxтЛЕ┬аy
When┬аx┬а=8 cm and┬аy┬а=6 cm,
Hence, the area of the rectangle isincreasing at the rate of 2 cm2/min.