1. 3.1 Lines and Angles Objective: Students will identify the relationships between 2 lines or 2 planes, and name angles formed by parallel lines and transversals.

2. Definitions Parallel Lines: coplanar lines that do not intersect Parallel Lines: coplanar lines that do not intersect Parallel Planes: planes that do not intersect Parallel Planes: planes that do not intersect Skew Lines: noncoplanar lines that do not intersect Skew Lines: noncoplanar lines that do not intersect Transversal: a line that intersects 2 or more lines in a plane at different points Transversal: a line that intersects 2 or more lines in a plane at different points

3. Transversals and Angles Consecutive Interior Angles: <3 & <6, <4 & <5 (also called same side interior angles) Consecutive Interior Angles: <3 & <6, <4 & <5 (also called same side interior angles) Alternate Exterior Angles: <1 & <7, <2 & <8 Alternate Exterior Angles: <1 & <7, <2 & <8 Alternate Interior Angles: <3 & <5, <4 & < 6 Alternate Interior Angles: <3 & <5, <4 & < 6 Corresponding Angles: <1 & <5, <2 & <6, <3 & <7, <4 &<8 Corresponding Angles: <1 & <5, <2 & <6, <3 & <7, <4 &<8 1 2 3 4 5 6 7 8

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6. 3.2 Properties of Parallel Lines Objective: Students will use the properties of parallel lines to determine congruent angles and angle measures.

7. Postulates and Theorems Corresponding Angle Postulate: If 2 || lines are cut by a transversal, then the corresponding <s are congruent. Corresponding Angle Postulate: If 2 || lines are cut by a transversal, then the corresponding <s are congruent. Alternate Interior Angle Thm: If 2 || lines are cut by a transversal, then alt. int. <s are congruent. Alternate Interior Angle Thm: If 2 || lines are cut by a transversal, then alt. int. <s are congruent. Consecutive Interior Angle Thm: If 2 || lines are cut by a transversal, then cons. Int. <s are suppl. Consecutive Interior Angle Thm: If 2 || lines are cut by a transversal, then cons. Int. <s are suppl. Alternate Exterior Angle Thm: If 2 || lines are cut by a transversal, then alt. ext. <s are congruent. Alternate Exterior Angle Thm: If 2 || lines are cut by a transversal, then alt. ext. <s are congruent.

8. Perpendicular Transversal Thm. In a plane, if a line is perpendicular to one of two || lines, then it is perpendicular to the other. In a plane, if a line is perpendicular to one of two || lines, then it is perpendicular to the other.

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