An airport X is due north of another airport Y.An aeroplane leaving X flies due south for 380km and airport y is now 50km away.How far is X from Y

Answer 1

380 + 50 (not there yet)
or
380 - 50 (flew right over it)

Answer 2

XZ = 380km.
YZ = 50km.

XY + YZ = XZ,
XY + 50 = 380,