Questions & Answers about Hipotez mantıklı.
You add the past-tense copula suffix -ydı (with a buffer vowel if needed):
Hipotez mantıklıydı
Literally “Hypothesis logical-was,” i.e. The hypothesis was logical.
Turkish has no direct equivalents of a/the. For an indefinite article you can use bir:
Bir hipotez mantıklı = A hypothesis is logical.
But when context is clear, you simply omit bir: Hipotez mantıklı.
Here mantıklı functions as a predicate adjective, not as an attributive adjective. Sentence structure is Subject + Predicate:
Hipotez (subject) + mantıklı (predicate).
If you want to say logical hypothesis as a phrase, you’d say mantıklı hipotez.