Unit 3 CONJECTURES (in order of appearance):
Complete and illustrate each of your new conjectures below. Be certain to add these to the
CONJECTURES section of your notebook on the day in which you complete the investigation(s) in
class.
ILLUSTRATION
CONJECTURE
Vertical Angles Conjecture
Linear Pair Conjecture
If two angles are vertical angles, then
________________________________.
If two angles are a linear pair of angles,
then ____________________________.
Equal Supplements Conjecture
If two angles are both equal in measure and
supplementary, then each angle measures
 Sum Conjecture
The sum of the measures of the three
interior angles of any triangle is _______.
( SUM = ____)
3rd Angle Conjecture
If two angles of one triangle are congruent
to two angles of another triangle, then
________________________________.
Quadrilateral Sum Conjecture
The sum of the measures of the t interior
angles of any quadrilateral is __________.
(QUAD SUM = ____)
Polygon Interior Sum
Conjecture
The sum of the measures of the interior
angles of any n-gon is _______________.
(POLYGON INTERIOR SUM = ______)
The measure of each interior angle of a
regular n-gon is ____________.
Polygon Exterior Sum
Conjecture
The sum of the measures of one set of
exterior angles of any n-gon is
_______________.
(POLYGON EXTERIOR SUM = ______)
Exterior Angle in a 
Conjecture
The measure of an (one) exterior angle in a
triangle _________________________.
Triangle Inequality
Conjecture
The sum of the lengths of any two sides in a
triangle is ________________________.
In a triangle, the ______________ side is
opposite the largest angle, and the
____________side is opposite the
smallest angle.
Isosceles  Conjecture
If a triangle is isosceles, then _________
________________________________.
(Isos.   base s _____)
Converse of Isosceles 
Conjecture
If two base angles of a triangle are
congruent, then ____________________.
(Base s   ______________)
Corresponding Angles
Conjecture
If two parallel lines are cut by a
transversal, then
(// lines  corres. s _____)
Converse of Corresponding
Angles Conjecture
If two lines are cut by a transversal
forming congruent corresponding angles,
then
(corres. s   __________)
Alternate Interior Angles
Conjecture
If two parallel lines are cut by a
transversal, then
(// lines  alt. int. s _____)
Converse of Alternate
Interior Angles Conjecture
If two lines are cut by a transversal
forming congruent alternate interior angles,
then
(alt. int. s   __________)
Alternate Exterior Angles
Conjecture
If two parallel lines are cut by a
transversal, then
(// lines  alt. ext. s _____)
Converse of Alternate
Exterior Angles Conjecture
If two lines are cut by a transversal
forming congruent alternate exterior
angles, then
(alt. ext. s   __________)
Same-Side Interior Angles
Conjecture
If two parallel lines are cut by a
transversal, then
(// lines  same-side int. s ______)
Converse of Same-Side
Interior Angles Conjecture
If two lines are cut by a transversal
forming same-side interior angles which are
supplementary, then
(same-side int.  supp. ______)
 Midsegment Conjecture
A midsegment in a triangle is
a. ______________________________
and
b. ______________________________.
Trapezoid Midsegment
Conjecture
A midsegment in a trapezoid is
a. ______________________________
and
b. ______________________________.