Geometry – Chapters 1 and 2 1-2 Points, Lines, and Planes Point Definition Line Name __________________________ Pd ____ Symbol Line Segment Endpoint Ray Plane Opposite Rays Space Collinear Points Coplanar Postulate or Axiom Postulate 1-1 Through any two points there is exactly one line. Intersection Postulate 1-2 If two distinct lines intersect, then they intersect in exactly one point. Postulate 1-3 If two distinct planes intersect, then they intersect in exactly one line. Postulate 1-4 Through any three noncollinear points there is exactly one plane. 1-3 Measuring Segments Postulate 1-5 Every point on a line can be paired with a real numbers. Ruler Postulate Distance between points Measuring Segment Lengths Postulate 1-6 Segment Addition Postulate If three points A, B, and C are collinear and B is between A and C, then AB + BC = AC. Segment Bisector Midpoint 1-7 Midpoint and Distance in the Coordinate Plane How to find the midpoint given 2 endpoints… How to find the other endpoint when given 1 endpoint and the midpoint… Distance Formula How to find the distance of a segment… Pythagorean Theorem 1-4 Measuring Angles Definition Symbol Angle Sides Vertex Interior region Exterior region Postulate 1-7 Protractor Postulate How to measure an angle… Every ray on an angle can be paired one to one with a real number from 0 to 180 on a protractor. Types of Angles Definition # of Degrees Acute Right Obtuse Straight Reflexive Congruent Angles Symbols for Congruent Angles Postulate 1-8 Angle Addition Postulate If point B is in the interior of <AOC, then m<AOB + m<BOC = m<AOC 1-5 Exploring Angle Pairs Special Angle Pairs Adjacent Angles Vertical Angles Supplementary Angles Complementary Angles Special Markings on Lines and Angles Linear Pair Definitions Angle #s Draw an example Postulate 1-9 Linear Pair Postulate Angle Bisector How to find angle measures using an angle bisector… If two angles form a linear pair, then they are supplementary. Geometry - Chapter 2 Name _________________________________ Pd ___ 2-5 Reasoning in Algebra and Geometry Algebraic Properties of Equality Addition Property Subtraction Property Multiplication Property Division Property Reflexive Property Symmetric Property Transitive Property Substitution Property Distributive Property Additive Inverse Property Multiplicative Inverse Property Additive Identity Property Multiplicative Identity Property Multiplicative Property of Zero Properties of Congruence Reflexive Property Symmetric Property Transitive Property Proof Two-Column Proof – Lists each statement on the left and the justification, or the reason for each statement, on the right. A convincing argument 2-6 Proving Angles Congruent Conjecture An “educated” guess, or a guess that you give thought to Theorem A conjecture or statement that you can prove true. Theorem 2-1 Vertical Angles Theorem Vertical angles are congruent. List the vertical angles: If … Then Statements Hypothesis The “if” part or conditional Conclusion The “then” part or the conclusion Paragraph Proof The statements and justifications are written in sentences in a paragraph instead of in two columns. Theorem 2-2 Congruent Supplements Theorem If two angles are supplements of the same angle (or of congruent angles), then the two angles are congruent. Theorem 2-3 Congruent Complements Theorem If two angles are complements of the same angle (or of congruent angles), then the two angles are congruent. Theorem 2-4 All right angles are congruent. Theorem 2-5 If two angles are congruent and supplementary, then each is a right angle.