Lexi started with line CD on her paper. She folded her paper so that point C was on top of point D. Then, she unfolded her paper and labeled the intersection of the fold and the line segment with point E. She used a straight edge to draw QR at an arbitrary angle through point E. Finally, she drew ↔CR through points C and R and ⟷DR through points D and R. Which line segment or line is the segment bisector in this scenario?

• ⟷QR
• ⟷CD
• ⟷DR
• ⟷CR

1 answer

In this scenario, Lexi folded the paper so that point C was on top of point D, which means that the fold is the perpendicular bisector of the line segment CD. When she unfolded the paper, point E is where the fold intersects the line segment CD.

She then drew a line QR through point E at an arbitrary angle, and also drew lines CR and DR through points C and R, and points D and R respectively.

Since E is the intersection point where the paper was folded (the perpendicular bisector of segment CD), the segment bisector of CD is indeed the line that runs through E, which is the line segment QR.

Therefore, the segment bisector in this scenario is:

• ⟷QR