Angle W:
180 = 90 + 57 + W
180 = 147 + W
W = 33 degrees
Using trigonometry functions to find the side lengths. (SOH CAH TOA)
Side XZ:
cos(57) = XZ / 18
XZ = cos(57) x 18
XZ = 9.8 units
Side XW:
sin(57) = XW / 18
XW = sin(57) x 18
XW = 15.1 units
Hope this helps!! :)