diff --git a/src/test/java/CalculationsTest.java b/src/test/java/CalculationsTest.java
index 9b6a1df..accfdae 100644
--- a/src/test/java/CalculationsTest.java
+++ b/src/test/java/CalculationsTest.java
@@ -10,5 +10,8 @@ public class CalculationsTest {
         // Test with a positive number
         assertEquals(25, calc.calculateSquare(5));
 
+        // Test with a negative number
+        assertEquals(16, calc.calculateSquare(-4));
+
     }
 }