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Math Postulates and Theorems (for 9th grade frezh!)
segment addition postulate
If B is between A and C, then AB+BC=AC
angle addition postulate
Angles can be added together if they are adjacent
, If P is in the interior of <RST, then m<RSP + m<PST = m<RST
linear pair theorem
if two angles form a linear pair, then they are supplementary
congruent supplements theorem
if two angles are supplementary to the same angle (or to congruent angles) then they are congruent
right angle congruence theorem
all right angles are congruent
congruent complements theorem
If two angles are complements of the same angle (or of congruent angles), then the two angles are congruent.
common segments theorem
Given collinear points A, B, C and D arranged as shown if line AB is congruent to line CD then line AC is congruent to line BD a__,__b_______c__,__d
vertical angles theorem
vertical angles are congruent
if a=b then b=a
if a=b and b=c then a=c
if a=b, then b can be substituted for a in any expression