diff --git a/calculator.py b/calculator.py
index c57b806..2954216 100644
--- a/calculator.py
+++ b/calculator.py
@@ -4,4 +4,7 @@ def add(a,b):
 
 # Add function
 def multiply(a,b):
-    return a * b
\ No newline at end of file
+    return a * b
+
+def subtract(a,b):
+    return a + b
diff --git a/test_calculator.py b/test_calculator.py
index b6219a5..ae115b5 100644
--- a/test_calculator.py
+++ b/test_calculator.py
@@ -28,4 +28,6 @@ def test_multiply():
 
    # could check squaring
 
-   # could check multiplying by 1
\ No newline at end of file
+   # could check multiplying by 1
+def test_subtract():
+    assert subtract(5, 3) == 2