Postulates and Theorems Flashcards
(12 cards)
Postulate 1
Ruler Postulate- The distance between any 2 points equals the absolute value of difference of their coordinates.
Postulate 2
Segment Addition Postulate: If B is between A and C, AB+BC=AC
Postulate 3
Through any two points, there is only one line.
Postulate 4
Angle Addition Postulate: If B lies in the interior of AOC, then (measure of angle AOB)+(Measure of angle BOC) = Measure of angle AOC
Postulate 5
A line contains at least two points, a plane contains at least three points not all in one line, and space contains at least 4 points, not all in one plane.
Postulate 6
Through any 2 points there is exactly 1 line.
Postulate 7
In any three points there is at least one plane, and through any three noncollinear points, there is exactly one point.
Postulate 8
If two points are in a plane, then the line containing them is also in the plane.
Postulate 9
If two planes intersect, their intersection is a line.
Theorem 1.1
If two lines intersect, they intersect at exactly at one point;
Theorem 1.2
Through a line and a point not on the line, there is exactly one plane. (Go back to postulate 7- any three noncollinear points make exactly one plane.
Theorem 1.3
If two lines intersect, then exactly one plane contains the lines. (Revisit postulate 7- through any three noncollinear points, there is exactly one plane.)