How many points do you need to determine a unique plane?
a plane is any plane surface it usually have 3 or 4 points
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You need only three points provided they are not collinear. And most planes have infinitely many points although there are geometries with only a finite number of points.
a line has to have at least 2 points. a plane has to have at least 3 points. ______________ It takes two points to define a unique line in Euclidean space. But every line and every line segment contains infinitely many points. The same is true for planes in Euclidean space. You need at least 3 points to define a unique plane, but every plane containes infinitely many points and infinitely many lines or line…
If you were to have 3 points on the same line, then you would actually not be determining a plane, because there are infinitely many planes that can intersect a given line. But if you have 3 points in the form of the points (or vertices) of a triangle, then you determine a plane in the sense that there is only one possible plane upon which that triangle can be drawn (not including a degenerate…
Any 3 geometric points, as long as they are all in different locations and not superimposed on each other, will define a plane. In other words, there is only one plane that can pass through 3 distinct points. If you had only two points, it would define a line, but not a plane. A plane can include 2 points but if there are only 2 that are specified, the plane can rotate around those 2…
A minimum of three points are required to define a plne (if they are not collinear). And in projective geometry you can have a plane with only 3 points. Boring, but true. In normal circumstances, a plane will have infinitely many points. Not only that, there are infinitely many in the tiniest portion of the plane.
In classical or Euclidean plane geometry two points defines exactly one line. On a sphere two points can define infinitely many lines only one of which will represent the shortest distance between the points. On other curved surfaces, or in non-Euclidean geometries, the number of lines determined by two points can vary. Even in the Euclidean plane, two points determine infinitely many lines that are not straight!
There are no planes containing any number of given points. Two points not the same define a line. Three points not in a line define a plane. For four or more points to lie in the same plane, three can be arbitrary but not on the same line, but the fourth (and so on) points must lie in that same plane.