CK12 - Geometry

Statement Reason

1. Lines and intersect. Given


2. and , and are linearpairs. Definitionof linearpairs


3. and are supplementary, and and are supplementary. LinearPair Postulate
   Supplementsof the Same
   AngleTheorem

4.

This showsthat. The sameproofcan be usedto showthat.

Example 2

Given: ,

Eachof the followingpairsof anglesare congruent.Give a reason.

and answer:VerticalAnglesTheorem

and answer:Complementsof CongruentAnglesTheorem

and answer:VerticalAnglesTheorem

and answer:VerticalAnglesTheorem

and answer:VerticalAnglesTheoremand TransitiveProperty

and answer:VerticalAnglesTheoremand TransitiveProperty

and answer:Complementsof CongruentAnglesTheorem

Example 3

• Given: ,


• Prove: