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Common Core

G-CO.C.9

5 lessons teach this standard. Every lesson is interactive, and every one prints as a worksheet with a separate answer key.

Geometry · Chapter 1 · Lesson 1

Definitions, Postulates, and Proof

What counts as an argument.

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Geometry · Chapter 1 · Lesson 2

Angle Pairs and Parallel Lines

A transversal makes eight angles and only two sizes.

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Geometry · Chapter 3 · Lesson 2

Writing a Two-Column Proof

Every claim carries its reason.

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Integrated Math 2 · Chapter 7 · Lesson 1

Inductive and Deductive Reasoning

How a pattern becomes a conjecture, and a conjecture becomes a theorem.

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Integrated Math 2 · Chapter 7 · Lesson 2

Angle and Triangle Theorems

The results a proof is built from.

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