Theorems
Postulate1-3--given AB and a # r between 0 and
180, there is exactly one ray w/
endpoint A, extending on each side of AB,
such that the measure of the angle
formed is r postulate1-4--if r is in the
interior of pqs, then Mpqr+Mrqs=Mpqs.if
Mpqr+Mrqs then R is in thr
interior of angle pqs postulate 2-2--through any 3
points not on the same
line there is exactly one plane law of detachment--if
P--*Q is a true
conditional and P is true, then Q is true law of syllogism--if
P--*Q and
Q--*R are true conditionals, then P--*R is also true
theorem2-1--congruence
of segments is reflexive, symmetric and transitive
theorem2-2--if 2 angles
form a linear pair, then they r supplementary angles
theorem2-3--congruence
of angles is reflexive, symmetric, and transitive
theorem2-4--angles
supplementary to the same angle or to the congruent angles r
congruent
theorem2-5--angles complementary to the same angle or to congruent
angles r
congruent theorem2-6--all right angles r congruent
theorem2-7--vertical
angles r congruent theorem2-8--perpindicular lines
intersect to form 4 right
angles skew lines-2 lines r skew if they don’t
intersect and r not in the same
plane postulate3-1-- if 2 // lines r cut by a
transversal, then each pair of
corresponding angles is congruent
theorem3-1--if 2 // lines r cut by a
transversal, then each pair of alternate
interior angles in congruent
theorem3-2--if 2 // lines r cut by a
transversal, then each pair of consec. int.
angles is supp. theorem3-3--if 2
// lines r cut by a transversal, then each pair
of alternate ext. angles is
congruent theorem3-4--in a plane, if a line is perp.
to 1 of 2 // lines, then
it is perp. to the other postulate3-4--2 nonvertical
lines have the same
slope if and only if they r //. postulate3-5--2 nonvertical
lines r perp. if
and only if the product of their slopes is -1 theorem4-3--the
measure of an
exterior angle of a triangle is equal to the sum of the measures
of the 2
remote interior angles CPCTC- 2 triangles r congruent if and only if
their
corresponding parts r congruent theorem4-4--congruence of triangles
is
reflexive, transitive and symmetric theorem4-6--if 2 sides of a triangle
r
congruent, then the angles opp. the sides r congruent theorem4-7--if 2
angles of
a triangle r congruent, then the sides opp. those angles r
congruent
theorem4-3--a triangle is equilateral if and only if it is
equiangular
theorem5-1 a point on the perp. bisector of a seg. is equidistant
from the
endpoints of the seg. theorem5-2--a point equidistant from the
endpoints of a
seg. lies in the perp. bisector of the seg. theorem5-3--a
point on the bisector
of an angle is equidistant from the sides of the angle
theorem5-4--a point in
the interior of or on an angle and equidistant from
the sides of an angle lies
on the bisector of the angle theorem5-5--if the
legs of 1 rt. triangle r
congruent to the corr. legs of another rt. triangle,
then the triangles r
congruent theorem5-6--if the hypotenuse and an acute
angle of 1 rt. triangle r
congruent to the hyp. and corr. acute angle of
another rt. triangle, then the 2
triangles r congruent theorem5-9--if 1 side
of a triangle is longer than the
other side,then the angle opp. the longer
side is greater than the angle opp.
the shorter side theorem5-11--the
perp.seg. froma point to a line is ythe
shortest seg. from the point to the
line theorem5-12--the sum of the lenghts of
any 2 sides of a triangle is
greater than the lenght of the third side
theorem6-1--opp. sides and angles
of a parallelogram r congruent theorem6-4--the
diagonals of a parallelogram
bisect each other theorem6-5--if both pairs of opp.
sides of a quad. r
congruent, the the quad is a parallelogram theorem6-6--if 1
pair of opp.
sides of a quad. r both parallel and congruent, then the quad. is
a
parallelogram theorem6-7--if the diagonals of a quad. bisect each other,
then
the quad. is a parallelogram theorem6-8--if both pairs of opp. angles in
a quad
r congruent,then the quad is a parallelogram theorem6-9--if a
paralellogram is a
rectangle then its diagonals r congruent theorem6-10--the
diagonals of a rhombus
r perp. theorem6-11--each diagonal of a rhombus
bisects a pair of opp. angles
theorem6-12--both pairs of base angles of an
isoceles trapezoid r congruent
theorem6-13--the diagonals of an isoceles
trapezoid r congrient theorem6-14--the
mediand of a trapezoid is parallel to
the bases and its measure is one half the
sum of the measures of the
bases.