level
I believe the word you wanted was 'obtuse'.
Planar.
They are said to be congruent
No. The word "quadrilateral" means "having four sides".
"I'll take your word for it" means that the person trusts and believes what you are saying without needing further proof or evidence. It implies that they will accept what you say as true based on your word alone.
Assumption
A statement accepted without proof is commonly known as a theorem. The other word that is used for such statements is postulate.
Postulate
allege
postulates
Achromatic means being without color or having no color.
I believe the word you're looking for is psychopath.
I believe the word you are looking for is non-uniformed school.
Achromatic means being without color or having no color.
state or assert that something is the case, typically without providing evidence or proof
It indicates the plural without having to write out a separate word.