diff --git a/Test-problems.md b/Test-problems.md
index 702f7e6..8d4790a 100644
--- a/Test-problems.md
+++ b/Test-problems.md
@@ -21,6 +21,10 @@ AD &\;=\;& BE &\;=\;& CF &\;=\;& r + s
 ```
 for some positive $r$, $s$. Show that $A$, $B$, $C$, $D$, $E$, $F$ must be the vertices of an equiangular planar hexagon.”
 
+#### Coverage
+
+At pull request #84, you can place six points in a rough planar hexagon, impose the distance constraints for some chosen $r$ and $s$, and see that the assembly becomes an equiangular planar hexagon, which seems to be rigid when you nudge the points.
+
 ## Exploring configuration spaces
 
 ### The configuration space of equiangular, equilateral hexagons