Decided and reached are past tense.
Computed is the past tense of compute.
The past perfect tense is had moved.
The past perfect tense is had come.
"Had flowed" is the past perfect tense of flow.
"Had flowed" is the past perfect tense of flow.
The past tense of decide is decided.
The infinitive would be "to decide", the present tense would be "decide(s)", and the past tense IS "decided". The word decided is the past tense. The present and future tense are (PRESENT) decides or decide and (FUTURE) will decide.
The past is reached.
The past tense of "reach" is "reached."
The past perfect tense of reach is had reached.
I think you mean "decide", which is "decided" in the past tense.
The past tense of "reach" is "reached" and the past participle is also "reached."
Reach the other is past tense
Decision is a noun. The verb form is decide, and the past tense is decided.
Decided
No, it is not a noun. Reached is the past tense and past participle of "to reach." The noun form is just "reach."
The word decided is a verb. It is the past tense of the verb decide.