Answer: 4th figure , where XY is a line.
Step-by-step explanation:
- There are 3 undefined terms : 1) point 2) line 3 ) plane
From up to down, The first figure is representing ray( end point at X ) which is an defined term and it is defined as "A ray is a line with one end point."
The second figure is representing a line segment with 2 end-points at X and Y and it is and defined term and it is defined as "A line segment is a line with 2 end points."
The third figure is a joint of two rays and they are making an angle which is again an defined term.
The last figure is representing a line which has no endpoints and is an undefined term.
Hence, the last figure is representing an undefined term "line".
