Parallel and Perpendicular Line Proofs

• You cannot prove.

• You can with Corresponding Angles Converse

• You can with Alternate Interior Angles Converse

• You can with Alternate Exterior Angles Converse

• You can with Consecutive Interior Angles Converse

• You cannot prove.

• You can with Corresponding Angles Converse

• You can with Alternate Interior Angles Converse

• You can with Alternate Exterior Angles Converse

• You can with Consecutive Interior Angles Converse

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• none

If AC ⊥ BD, then ∠DBC is a right angle.

• Definition of Perpendicular Lines

• Definition of Right Angle

• Angle Addition Postulate

• Segment Addition Postulate

• Linear Pair Perpendicular Theorem

• Perprendicular Transversal Theorem

• Lines Perpendicular to a Transversal Theorem

• Linear Pair Perpendicular Theorem

• Perprendicular Transversal Theorem

• Lines Perpendicular to a Transversal Theorem

Slopes of parallel lines are...

• opposite reciprocals.

• opposites.

• the same 

• always 7.

Slopes of perpendicular lines are...

• opposite reciprocals.

• opposites.

• identical.

• always 7.