from xy = x + 4
x dy/dt + y dx/dt = dx/dt + 0
when x = 4 , in original
4y = 4+4
y = 2
so when x=4, y=2 and dx/dt = -5
4dy/dt + 2(-5) = -5 + 0
4dy/dt = 5
dy/dt = 5/4 which is c)
Assume that x and y are differentiable functions of t. Find dy/dt using the given values.
xy=x+4 for x=4, dx/dt=-5
a. 0.20
b. 3.75
c. 1.25
d. 5.00
e. -0.25
2 answers
is it C. or D.