Answer
a) dy/dt = 3/4
b) dx/dt = 20
Work Step by Step
$ y = \sqrt(x) $
$\frac{d}{dt} (y) = \frac{d}{dt} \sqrt(x) $
$1 \frac{dy}{dt} = \frac{1}{2\sqrt(x)}\frac{dx}{dt}$
a) Find dy/dt when x = 4 and dx/dt = 3 then
$1 \frac{dy}{dt} = \frac{1}{2\sqrt(4)}(3) = (1/4)*3 = 3/4 $
b) Find dx/dt when x = 25 and dy/dt = 2
$2 = \frac{1}{2\sqrt(25)}\frac{dx}{dt}$
$\frac{dx}{dt} = 4(5) = 20 $