Finally, we know , so both of the anglesmeasure47º.AngleBisectors
If a segmentbisectordividesa segmentinto two congruentparts,you can probablyguesswhatanangle
bisectoris. An anglebisectordividesan angleinto two congruentangles,eachhavinga measureexactly
half of the originalangle.
AngleBisectorPostulate:Everyanglehas exactlyone bisector.
Example 5
The anglebelowmeasures136º.If a bisectoris drawnin this angle,whatwill be the measureof the new anglesformed?This is similarto the problemaboutthe midpointbetweenthe two houses.To find the measurementsof the
smalleranglesoncea bisectoris drawn,dividethe originalanglemeasureby 2:
So, eachof the newlyformedangleswouldmeasure68º whenthe 136º angleis bisected.LessonSummary
In this lesson,we exploredsegmentsand angles.Specifically, we havelearned:
- How to understandand identifycongruentline segments.
- How to identifythe midpointof line segments.
- How to identifythe bisectorof a line segment.
- How to understandand identifycongruentangles.
- How to understandand applythe AngleBisectorPostulate.