Here, we want to prove that XWV and XYZ is similar
We proceed as follows;
1) WX = XZ; and VX = XZ
Reason; Given that X is the midpoint of WY and VZ
2) angle VXW and YXZ are equal
Reason; They are vertically opposite angles
Thus, we have two equal sides and an equal angle
The angle is between the two sides; this mean that the triangles are equal according to Side-Angle-Side (SAS)