We can draw the positions of each person as this:
The positions form a right triangle, of which we know one of the legs and the hypotenuse. We have to find the other leg, that is the distance between Haley and Felix.
We can calculate D, the hypotenuse, using the Pythagorean theorem:
![\begin{gathered} 12^2+L^2=20^2 \\ L^2=20^2-12^2 \\ L^2=400-144 \\ L^2=256 \\ L=\sqrt[]{256} \\ L=16 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/tnea2isjvvfji9jmvca5bsug6pd659em27.png)
Answer: Felix and Haley are approximately 16 meters apart.