Harry and selma start driving from the same location. harry drives 42 miles north while selma drives 144 miles east. how far apart are harry and selma when they stop?

When they stop, the point from the origin to where Harry is to where Selma is forms a right triangle, where the distance between the two people is equal to the hypotenuse.
Use the pythagorean formula to find the length of the hypotenuse.

42^2+144^2=c^2
22500=c^2
150=c

Final 150 miles