Geometry

angle bisector
angles bisector is the line that divides an angle into two congruent angles.

the first is "all statement" and the second is " existential statement"

all of them are collinear

they lie in the same plane

True
It is true that the body of an indirect proof you must show that the assumption leads to a contradiction. In math a proof is a deductive argument for a mathematical statement.

I dont think that "If four points are collinear they are also coplaner," is the same thing as "If four points are coplaner they are also collinear,". The definition of collinear is at least three points on the same line. To define a plane is to have threenoncollinear points.

A conclusion provided by deductive reasoning

It means "measure". So m<AVB is saying "the measure of Angle AVB is/= ? degrees".

The term that best describes a proof in which you assume the opposite of what you want to prove is 'indirect proof'.

In a two-column proof, it is true that the left column states your reasons.

hashmarks

Is PQ |_ RS

A plane.

FED and DEF lol

No, they are not.

Points are the only such objects.

It is known as the midpoint of the line segment

It could be, but without the diagram it is not possible to be certain.

CD

Corollary.

Theorem.

Definition.

Postulate.