In a federal system in government (also known as federation) the local and state governments share power with the central government, though the central has finally authorized. explain how this is different from a unitary system of government?

I think you mean "authority" not "authorized.

http://guides.skylinecollege.edu/content.php?pid=396928

what is it help

i did idk please help

Is it the Unitary System?

Please read the link I posted above.

It has your answer.

If you don't understand the simple chart in that website, you are beyond any help I can give you.

They are different because the federal is sharing power and the confederal is leading.