Draw six segments that pass through every dot in the figure without taking your pencil off the paper. INF Session 2 Have Your Homework On Your Desk!

Agenda Session 2 Warm-Up Homework ?s Finish Notes 1.2 Notes 1.3 & 1.4 Practice Work Tues 8/16 Quiz 1.1 – 1.4 Get textbooks Thurs 8/ & 2.1

Write down textbook name on textbook form. Geometry Concepts and Applications RED and BLUE Staple CALCULATOR form on TOP.

Informal Geometry Session 2 Complete 1.2 and begin 1.3 & 1.4

COPLANAR Points lie in the same plane NONCOPLANAR Points do NOT lie in the same plane Start 4 th period here

Has a beginning and an end Name a line segment by using the endpoints only You will always use two letters to name a segment Symbol or Segment Name of this segment:

Has a beginning but no end Starting pt. of a ray is called the endpoint Name a ray by using the endpt. 1st and another point on the ray You will always use two letters to name a ray Symbol or Ray Names of this ray: Start 7 th period here

What Do You See? A D C B Points: A, B, C, D Line: AD Ray: DB Segment: BD

Worksheet 1.2 Work quietly with a neighbor We will go over these

1.3 Postulates Postulates are facts about geometry that are accepted as true.

Postulate 1-1 Two points determine a line. There is only one line that contains points P and Q. PQPQ

Example 1 Points, C, A, and R are noncollinear. Name all the different lines that can be drawn. (Only name a line once.)

Postulate 1-2 If two distinct lines intersect, then their intersection is a point. Lines l and m intersect at point T. lmTlmT

Example 2 Name the intersection of.

Postulate 1-3 Three noncollinear points determine a unique plane. There is only one plane that contains points A, B, and C. ABCABC

EXAMPLE 3 H R l M F T A W V g TRUE or FALSE: There is only one plane that contains all of the points F, T, & M TRUE

EXAMPLE 4 A F ED C B G H Name all of the planes that are represented in the prism.

Postulate 1-4 If two distinct planes intersect, then their intersection is a line.

EXAMPLE 5 A F ED C B G H Name the intersection of plane ABH and plane DCG. CB

Classwork Practice Worksheet 1.3

Conditional Statements Called if-then statements. Hypothesis- The part following if. Conclusion- The part following then. * Do not include if and then in the hypothesis and conclusion.

Hypothesis and Conclusion If you are not satisfied for any reason, then return everything within 14 days for a full refund.

Try These If it is Saturday, then Elise plays soccer. –Hypothesis- –Conclusion- If points are collinear, then they lie on the same line. –Hypothesis- –Conclusion- it is Saturday Elise plays soccer points are collinear they lie on the same line

Converse The converse of a conditional statement if formed by exchanging the hypothesis and the conclusion in the conditional. –Conditional- If a figure is a triangle, then it has three angles. –Converse- If a figure has three angles, then it is a triangle.

* The converse does not have to be true. Conditional- If a figure is a square, then it has four sides. Converse- If a figure has four sides, then it is a square. * Not all four sided figures are squares. Rectangles also have four sides.

Rewrite the statement as a conditional statement, then find the converse. All members of Congress are U.S. citizens. Conditional- Converse- If you are a member of Congress, then you are a U.S. citizen. If you are a U.S. citizen, then you are a member of Congress.

Classwork Practice Worksheet 1.4 –HW finish 1.3 & 1.4 ws QUIZ NEXT CLASS!! 1.1 – 1.4