Warm Up 09.22.11Week 6

1) State the postulate that shows the statement to be false:

A line contains at least three points.

Geometry

2.2 Day 1

I will recognize and use definitions.

Definitions Previous knowledge used to explain your answers.

Ex 1

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Is the statement true or false: Explain.

D,X, and B are collinear.

True. 2 or more points are collinear if they lie on the same line. D,X, and B all lie on DB so they are collinear.

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Do 1:

∠ AXB is adjacent to ∠ CXD

False. By definition adjacent angles must share a common side. ∠ AXB and ∠ CXD do not share a common side so they are not adjacent.

Answer

True or False:

1st Sentence: True or False2nd Sentence: Definition3rd Sentence: Describe why definition proves the graph

Biconditional Statement

A statement that contains the phrase “if and only if”.

Ex 3

Three lines are coplanar if and only if they lie in the same plane.

Conditional Statement: if three lines are coplanar, then they lie in the same plane.

It is a conditional statement and its converse.

Converse: if three lines lie in the same plane then they are coplanar.

Do: 2 ∠ AXB is vertical to ∠ BXC

Assignment:

Textbook Page 82, 13 – 23 All and 59 – 68 All.

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