A rectangle initially has dimensions 4cm by 6cm. All sides begin increasing in length at a rate of 5cm/s. At what rate is the area of the rectangle increasing after 15 seconds

Answer 1

area = x y
x = 4 + 5 t
y = 6 + 5 t
A = (4+5t)(6+5t) = 24 + 50 t + 25 t^2
dA/dt = 50 + 50 t
now try t = 15

original area = 4*6 = 24

4 + 5*15 =

Answer 2

Thank you so much!

Answer 3

You are welcome.