CK12 - Geometry

3. [Diff: 1]


4. The slopeof and the slopeof both = 0 since the linesare horizontal. For ,
   . Finallyfor ,
   [Diff: 2].


5. Sincethe slopesof the oppositesidesare equal,the oppositesidesare parallel.Therefore, is
   a parallelogram[Diff: 2].


6. Usingthe distanceformula,

Since is a parallelogram,we knowthat [Diff: 2].

7. and [Diff: 2]


8. First,we convertthe theoreminto “given”informationand whatwe needto prove:Given:Parallelogram

.

Prove: and

Statement Reason

1. ABCDis a parallelogram 1. Given
   2. Drawauxiliarysegment and labelthe anglesas2. Line Postulate
   follows


2. Definitionof parallelogram


3. 
   


4. 
   
   
   
   4. AlternateInteriorAnglesTheorem