Answer:
The proposition If Y is the midpoint of XZ, then XY = 1/2 XZ is true.
Step-by-step explanation:
We proceed to present the demonstration of the following proposition:
If Y is the midpoint of XZ, then XY = 1/2 XZ.
1) Y is the midpoint of XZ. Given.
2) [tex]XY + YZ = XZ[/tex] Definition of line segment.
3) [tex]XY = YZ[/tex] By 1)
4) [tex]2\cdot XY = XZ[/tex] 3) in 2)
5) [tex]XY = \frac{1}{2}\cdot XZ[/tex] Algebra/Result
Therefore, the proposition If Y is the midpoint of XZ, then XY = 1/2 XZ is true.