beach

Problem 19
A man on an island a miles south of a straight beach wishes to reach a point on shore b miles east of his present position. If he can row r miles per hour and walk w miles per hour, in what direction should he row, to reach his destination as soon as possible? See Fig. 57.
 

Problem 69
A man on an island 12 miles south of a straight beach wishes to reach a point on shore 20 miles east. If a motorboat, making 20 miles per hour, can be hired at the rate of \$2.00 per hour for the time it is actually used, and the cost of land transportation is \$0.06 per mile, how much must he pay for the trip?