1. + OBJECTIVE: to use postulates and undefined terms DO NOW: REVIEW FOR QUIZ HOMEWORK FOR MONDAY: TEXTBOOK PG. 17 # 16, 18, 22, 26, 32, 34, 36, 42, 44, 50 AND 52

2. + Homework check 1. Odd 2. 10 3. Counterexample: the product of two negative numbers is POSITIVE (e.g.: -1(-2)=2) 4. Counterexample: number with a “5” in the ones spot are divisible by “5” but they are NOT divisible by “10”. (e.g.: 45/5 = 9….45/10 does NOT equal a whole number.) 5. Counterexample: these circles are touching each other yet one is not inside the other

3. + IMPORTANT VOCABULARY UNDEFINED TERM: A word, such as point, line, or plane that is not mathematically defined using other known words, although there is a common understanding of what the word means. POINT: It has no dimension and is represented by a small dot. LINE: It has one dimension and extends without end in two directions. It is represented by aline with two arrowheads. PLANE: It has two dimensions. It is represented by a shape that looks like a floor or wall. POSTULATE: statement that is accepted without further justification. COLLINEAR POINTS: Points that lie on the same plane. COPLANAR POINTS: Points that lie on the same plane. COPLANAR LINES: Lines that lie on the same plane. ENDPOINTS: Two points on either side of a line segment. LINE SEGMENT: A part of a line that consists of two points, called endpoints, and all points on the same line that are between the endpoints. RAY: It consists of the endpoint A and all points that lie on the same side of A as B.

4. + POSTULATE 1: TWO POINTS DETERMINE A LINE n Line n passes through points P and Q WordsSymbols P Q Through any two points there is exactly one line

5. + POSTULATE 2: THREE POINTS DETERMINE A PLANE Through any two THREE NONCOLLINEAR points there is exactly ONE PLANE. Plane T passes through points A, B and C. WORDSSYMBOLS A B C T

6. + KHAN ACADEMY VIDEO KHAN ACADEMY POINTS, LINES AND PLANES

7. + CLOSING HOW DID YOU DO ON THE QUIZ? DID YOU ADEQUATELY PREPARE? IF YOUR ANSWER IS NO: WHAT CAN YOU DO BETTER NEXT TIME? CHECK, + OR – for understanding