Postulates and theorems U1 Flashcards
Postulate 2
Midpoint = B. AB+CB=AC
Postulate 4
If point b is in the interior of AOC, then aob +boc =aoc
postulate 5
a line contains 2 points, a plane contains 3 points not in a line, and space has 4 points
postulate 6
there is exactly one line between any two points
Postulate 7
There is at least one plane through any three points. for non collinear points there is exactly one
postulate 8
if two points are on a plane, then the line containing them is on the same plane
postulate 9
where two planes intersect, there is a line
theorem 1-1
if two lines intersect, it is in exactly one point
theorem 1-2
through a line and a point not in the line, there is exactly one plane
theorem 1-3
if two lines intersect, they are contained within exactly one plane
complimentary angles
two angles that add up to 90
supplementary angles
two angles that add up to 180
Reflex angle
an angle whose measure is greater than 180 degrees and less than 360 degrees
Straight angle
exactly 180 degrees
vertical angles
two angles across from each other, always congruent
adjacent angles
2 angles next to each other w a common side, common vertex and no common inner points
linear pair
2 angles that are adjacent and supplementary. make a straight line
complementary angles
any TWO angles that have a sum of 90
supplementary angles
any TWO angles that have a sum of 180
