Problems plotting an implicit solution to a differential equation

I am trying to plot the implicit solution to a differential equation, but fimplicit comes up with an error. The code is

clear all
syms y(x)
eqn = diff(y) == (2*x+y+2)/(2*x+y-4);
solutions = dsolve(eqn,Implicit=true)

solutions = 

impl = subs(solutions(1),[sym("C1"),x],[0,x])

impl = 

fimplicit(impl)

Warning: Error in state of SceneNode.
Unable to convert symbolic expression to double array because it contains symbolic function that does not evaluate to number. Input expression must evaluate to number.

The solution to the differential equation is correct. I am afraid I don't understand the error message for fimplicit...

Answer 1

[Torsten]

For more complicated cases where an explicit solution cannot be found:

syms y(x)
eqn = diff(y) == (2*x+y+2)/(2*x+y-4);
solutions = dsolve(eqn,Implicit=true)

solutions = 

syms u
impl1 = subs(lhs(solutions(1))-rhs(solutions(1)),[sym("C1"),y],[0,u]);
[impl2,~] = numden(lhs(solutions(2)));
impl2 = subs(impl2,y,u);
impl1 = matlabFunction(impl1,'Vars',[x,u])

impl1 = function_handle with value:
    @(x,u)u-x-log(u+x.*2.0-2.0).*2.0+2.0

impl2 = matlabFunction(impl2,'Vars',[x,u])

impl2 = function_handle with value:
    @(x,u)u+x.*2.0-2.0

hold on
fimplicit(impl1)
fimplicit(impl2)
hold off
grid on

[Georg]

Thanks. That's great (and more complicated than I would have guessed).

Answer 2

[Walter Roberson]

syms y(x)
eqn = diff(y) == (2*x+y+2)/(2*x+y-4);
solutions = dsolve(eqn,x)

solutions = 

impl1 = subs(solutions(1),[sym("C1"),x],[0,x])

impl1 = 

●

impl2 = solutions(2)

impl2 = 

fplot([impl1, impl2], [1 3.5])

[Georg]

The problem with the explicit answer is that it is only plotted up to the point where the tangent becomes vertical. I was suspecting that it continues on, and Torsten's answer above shows that.