Question

A table with four legs will sometimes wobble if one leg is shorter than the other three, but a table with three legs will not wobble. Select the postulate that substantiates this fact.
Postulate 1: A line contains at least two points.
Postulate 1a: A plane contains at least three points not all on one line.
Postulate 1b: Space contains at least four points not all on one plane.
Postulate 2: Through any two different points, exactly one line exists.
Postulate 3: Through any three points that are not one line, exactly one plane exists.
Postulate 4: If two points lie in a plane, the line containing them lies in that plane.
Postulate 5: If two planes intersect, then their intersection is a line.

Answer 1

Postulate three is the correct reason for this

Answer 2

The Postulate 3 will be followed up that says

“Through any three points that are not one line, exactly one plane exists.”

The four-legged table will not get the perfect balance among the plane while the three legs will get the balance to stand on a single plane easily without wobbling.