How can I solve this related Rates problem?

Question

A computer program increases the side of a square image on the screen at a rate of 0.25 inches/sec. Find the rate at which the Area of the image increases when the edge is 6.50 in.

Answer 1

Area= (side)^2
A=s^2
Rate of change of Area dA/dt = 2s ds/dt

ds/dt = 0.25 inches/sec. (given)
at s=6.50 inch (given)
dA/dt=2*6.50*0.25
=3.25 sq. in./sec.

Answer 2

f = x^2
f' = 2x = 11 in/sec