LTV observable?

If LTV system: d(x)/dt=A(t)*x y=C(t)*x is observable,
then LTV system:
d(x)/dt= - A(t)*x y=C(t)*x
must be observable or not?
a counterexample to indicate the second system is not necessarily observable is enough.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.