Verified answer

y′=2(4−y) and y'=k(M-y)

--->k=2 , M=4

y = 4 + Ae^(-2t)

y(1) = 10 ---> A = ...

hence

y(0) = ..

y′=2(4−y) and y(1)=10

Change the variable z= 4-y, dz/dt =-dy/dt

dz/dt= -2z. z = z0 exp (-2t)

4-y= z0 exp(-2t). The solution is y = 4 - z0 exp - 2t

y(1) =10 t=1

10 = 4 -z0 exp-2, z0 = -6 exp 2

y=4 +6 exp(2-2t). y(0)= 4+6 exp 2