Isaiah walks 3 miles due north, turns and then 5 miles due east. how far is he from his starting point?

The two segments of his walk can be considered the two legs
of a right triangle.

His distance from his starting point is the hypotenuse of the triangle,
so to find its length, we can call on Old Man Pythagoras to help us.

         Distance²  =  (3)² + (5)²

         Distance  =  √(9 + 25)  =  √34

                                            =  5.831 miles  (rounded) .