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

Isiah is 5.83 miles away from his starting point.

When you draw the the miles Isaiah walks, you will discover that you are forming a right angle triangle.

To measure the length from the starting point to the ending point. We must used the Pythagorean equation. Where in the square of the hypotenuse is equal to the sum of squares of the other two sides.

a² + b² = c²

a = 3 miles                        3² + 5² = c²
b = 5 miles                        9  + 25 = c²
c = hypotenuse.                    34    = c²
 
We must get the hypotenuse, since 34 is the square of the hypotenuse we must look for its square root.

c² = 34
c = √34
c = 5.83 miles