diff --git a/test/Praktikum3/TriangleCheckerTest.java b/test/Praktikum3/TriangleCheckerTest.java
index dc0c257..4d94dc5 100644
--- a/test/Praktikum3/TriangleCheckerTest.java
+++ b/test/Praktikum3/TriangleCheckerTest.java
@@ -13,5 +13,6 @@ class TriangleCheckerTest {
         assertEquals(TriangleChecker.TriangleType.EQUILATERAL, TriangleChecker.checkTriangle(3, 3, 3 ));
         assertEquals(TriangleChecker.TriangleType.NONE, TriangleChecker.checkTriangle(5,-1,13));
         assertEquals(TriangleChecker.TriangleType.NONE, TriangleChecker.checkTriangle(0,3,13));
+        assertEquals(TriangleChecker.TriangleType.NONE, TriangleChecker.checkTriangle(5,9,-13));
     }
 }
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