Answer:
14.14
Explanation:
Recall :
The sides of a square are always equal ;
Since all sides are equal, the the diagonal of the square will be :
XZ² = XY² + WX²
XZ² = 20² + 20²
XZ² = 400 + 400
XZ² = 800
XZ = √800
XZ = 28.28
WY = XZ
WV = 1/2 WY
WV = 1/2 * 28.28
WV = 14.14