Triangle Angle Bisector Theorem Worksheet with Answer Key

What's on the worksheet

1. Decide which proportions must be true for an angle bisector without using lengths.
   \dfrac{KN}{NM} = \dfrac{LK}{LM}\dfrac{KN}{NM} = \dfrac{LM}{LK}\dfrac{KN}{LK} = \dfrac{NM}{LM}\dfrac{KN}{NM} = \dfrac{LK}{KM}\dfrac{KN}{KM} = \dfrac{LK}{LK + LM}
2. Find how the spotlight bisector splits the stage edge from the side walls and perimeter.
3. Find BD, DC and BC when the pieces differ by 3.
4. Show the bisector lies along y = x, then find where it meets BC.
5. Explain from Jin's answer that his proportion is upside down.
6. Find the point where the exterior angle bisector meets the line BC.
7. Find BD, DC and AD in a triangle where one angle is twice another.