Question 1096345
<br>He walked a total of 24km east, and he ends up 25km from where he started.  Using the Pythagorean Theorem tells us he ends up either 7km north or 7km south of where he started.<br>
So if at one point he walked 15km north, then he has to walk either x=8km south, to reach a point 7km north of where he started, or x=22 km south, to reach a point 7km south of where he started.<br>
So two answers:  x=8 or x=22.