diff --git a/rtiow/src/bin/tracer_norm_shade.rs b/rtiow/src/bin/tracer_norm_shade.rs
index 7f65e77..88a6484 100644
--- a/rtiow/src/bin/tracer_norm_shade.rs
+++ b/rtiow/src/bin/tracer_norm_shade.rs
@@ -13,7 +13,7 @@ fn hit_sphere(center: Vec3, radius: f32, r: Ray) -> f32 {
     if discriminant < 0. {
         return -1.;
     }
-    -b - discriminant.sqrt() / (2. * a)
+    (-b - discriminant.sqrt()) / (2. * a)
 }
 
 fn color(r: Ray) -> Vec3 {