3.4 Proofs with Perpendicular Lines

Finding the Distance from a Point to a Line

• The length of a perpendicular segment from a point to a line is considered the distance from a point to that line.

L

Vocabulary

Perpendicular Bisector1) Is perpendicular to the line it intersects. 2) Cuts the line in half.

Linear Pair Perpendicular Theorem

Given: <ADC = <CDBProve: Segment CD is perpendicular to Segment AB.

Perpendicular Transversal Theorem

Given: GF||AB and EC is perpendicular to GF.

Prove: EC is perpendicular to AB.

Lines Perpendicular to a Transversal Theorem

Given: EC is perpendicular to GF and also AB

Prove: GF||AB