-lie in the same plane
-are collinear
No, a line cannot contain four non-coplanar points. By definition, coplanar points are points that lie in the same plane, and any three points determine a plane. Since a line consists of an infinite number of points that are linear, any additional point beyond two points on a line will not be able to create a non-coplanar arrangement with those already on the line. Thus, four points on a line must be coplanar.
No. A trinagle does not require four points, three are sufficient. And any three points, if they are not colinear, must be coplanar.
not necassarily
space
life
all of them are collinear they lie in the same plane
No. If the four points are coplanar, they determine only one plane!
They need not be. The four vertices of a quadrilateral are coplanar but NOT collinear. On the other hand, any line (in Eucledian geometry) has an infinite number of points on it - all of which are coplanar.
Three points are, but not four.
No. A trinagle does not require four points, three are sufficient. And any three points, if they are not colinear, must be coplanar.
No, they always are From Wikipedia.org, "The World's Encyclopedia" when I searched coplanar In geometry, a set of points in space is coplanar if the points all lie in the same geometric plane. For example, three distinct points are always coplanar; but four points in space are usually not coplanar. Since 3 points are always coplanar. A point and line are always coplanar
not necassarily
space
life
Yes, they are.
Yes, they are.
If they lie in the same plane.