I am determined to succeed. He was relaxed in his easy chair.
Determined and relaxed are a past participles. They are used as adjectives to describe the subjects (I / He)
Past participles are frequently used as (predicate) adjectives. They are very often used with the verb "be", such as:
I am happy.
Regular adjective:
He had a determined look on his face.
Here are some active / passive pairs with transitive verbs:
The bad news stunned me. (active)
I was stunned by the bad news. (passive)
The sound of the shots startled the deer. (active)
The deer was startled by the sound of the shots. (passive)
The startled deer ran away. (startled is an adjective).