first, we must find 2z(dz/dt)=2x(dx/dt) + 2y(2y/dt) simplifying, we get: dy/dt=???(dx/dt + dy/dt)

Question

What is that simplified?

Answer 1

dividing by 2, we have

zz' = xx'+yy'

y' = (zz'-xx')/y

not sure where you're going with this

Answer 2

the problem was: 2z dz/dt= 2x dx/dt + 2y dy/dt

dz/dt= ??? ( x dx/dt + y dy/dt)

Answer 3

still confused

Answer 4

c'mon this is algebra I, after doing the derivatives. Just divide both sides by 2z:

dz/dt = (x dx/dt + y dy/dt)/z