Geometry Ch 1.1 Notes Conjecture – is an unproven statement that is based on observation Inductive Reasoning – is a process used to make conjectures by looking at patterns Counterexample – is an example that show a conjecture is false

Geometry Notes Ch 1.2 Undefined Terms – we just describe them Point – has no dimension, represented by a small dot, (position in space) Line – extends in one dimension, represented by a straight line with arrows on each end Plane – extends in two dimensions, represented by a parallelogram

Point Plane Ray Opposite Rays Line Line Segment

Definitions Collinear Points – are points all on the same line Coplanar Points – are points all of the same plane Intersect – if two or more figures have one or more points in common Intersection – is the set of points the figures have in common

Geometry Ch 1.3 Notes Postulates or Axioms – are rules that are accepted without proof Theorems – are rules that have been proven Lengths are equal Segments are congruent AB = AD AB = AD “is equal to” “is congruent to”

Postulate 1 – without the bar means length AB with the bar means line segment. The distance between two points is the absolute value of the difference of the coordinates. Postulate 2 – Segment Addition Postulate

Distance Formula - Pythagorean Theorem -

Geometry Ch 1.4 Notes Angle – consists of 2 different rays that have the same initial point Measures are equal Angles are congruent

Postulate 4 – Angle Addition Postulate Classifying angles by their measure Acute angle – Right angle – Obtuse angle – Straight angle –

Adjacent Angles – are 2 angles that share a common vertex and side, but do not have any common interior points in common

Geometry Ch 1.5 Notes Midpoint – is the point that divides a segment in half Bisect – means to cut into two equal parts Midpoint Formula – Angle Bisector -

Geometry Ch 1.6 Notes Vertical Angles – are 2 angles whose sides are opposite rays of each other. Linear Pair – 2 adjacent angles whose noncommon sides are opposite rays Complementary Angles – Supplementary Angles -

Geometry Ch 1.7 Notes Square - P = A = Rectangle – P = Triangle - P = Circle - C =