diff --git a/assignment-1/src/ray.rs b/assignment-1/src/ray.rs
index c010cd8..0adfef6 100644
--- a/assignment-1/src/ray.rs
+++ b/assignment-1/src/ray.rs
@@ -74,7 +74,7 @@ mod tests {
 
     let point = ray_intersection_time(&ray, &sphere).map(|t| ray.eval(t));
 
-    // the intersection point in this case is (0, 0, –6)
+    // the intersection point in this case is (0, 0, -6)
     assert_eq!(point, Some(Vec3::new(0.0, 0.0, -6.0)));
   }