diff --git a/raytracing/src/matrix.cpp b/raytracing/src/matrix.cpp
index dee8ec8..9a66723 100644
--- a/raytracing/src/matrix.cpp
+++ b/raytracing/src/matrix.cpp
@@ -208,16 +208,16 @@ double Matrix::determinant(void)
 
 /* ------------------------------------------------------------------------- */
 
-Matrix Matrix::sub_matrix(uint8_t a_rows, uint8_t a_cols)
+Matrix Matrix::sub_matrix(uint8_t a_row, uint8_t a_col)
 {
     Matrix the_sub = *this;
 
-    the_sub.m_data.erase(the_sub.m_data.begin() + a_rows);
+    the_sub.m_data.erase(the_sub.m_data.begin() + a_row);
     the_sub.m_rows--;
 
     for (int the_row = 0; the_row < the_sub.m_rows; the_row++)
     {
-        the_sub.m_data[the_row].erase(the_sub.m_data[the_row].begin() + a_cols);
+        the_sub.m_data[the_row].erase(the_sub.m_data[the_row].begin() + a_col);
     }
     the_sub.m_cols--;
 
@@ -226,9 +226,23 @@ Matrix Matrix::sub_matrix(uint8_t a_rows, uint8_t a_cols)
 
 /* ------------------------------------------------------------------------- */
 
-double Matrix::minor(uint8_t a_rows, uint8_t a_cols)
+double Matrix::minor(uint8_t a_row, uint8_t a_col)
 {
-    return sub_matrix(a_rows, a_cols).determinant();
+    return sub_matrix(a_row, a_col).determinant();
+}
+
+/* ------------------------------------------------------------------------- */
+
+double Matrix::cofactor(uint8_t a_row, uint8_t a_col)
+{
+    int8_t an_inverter = 1;
+
+    if ((a_row + a_col) % 2 != 0)
+    {
+        an_inverter = -1;
+    }
+
+    return an_inverter * minor(a_row, a_col);
 }
 
 /* ------------------------------------------------------------------------- */
diff --git a/raytracing/src/matrix.h b/raytracing/src/matrix.h
index bdd946f..068bb94 100644
--- a/raytracing/src/matrix.h
+++ b/raytracing/src/matrix.h
@@ -61,8 +61,9 @@ namespace Raytracer
 
         bool transpose(void);
         double determinant(void);
-        Matrix sub_matrix(uint8_t a_rows, uint8_t a_cols);
-        double minor(uint8_t a_rows, uint8_t a_cols);
+        Matrix sub_matrix(uint8_t a_row, uint8_t a_col);
+        double minor(uint8_t a_row, uint8_t a_col);
+        double cofactor(uint8_t a_row, uint8_t a_col);
 
         static Matrix identity(void);
 
diff --git a/tests/03_matrix.cpp b/tests/03_matrix.cpp
index bae341b..1e3c32e 100644
--- a/tests/03_matrix.cpp
+++ b/tests/03_matrix.cpp
@@ -294,3 +294,19 @@ TEST_CASE("[Matrix] Calculating a minor of a 3x3 matrix", "[Matrix]")
 
     REQUIRE(a.minor(1, 0) == 25);
 }
+
+/* ------------------------------------------------------------------------- */
+
+TEST_CASE("[Matrix] Calculating a cofactor of a 3x3 matrix", "[Matrix]")
+{
+    Matrix a = {
+        {3,  5,  0},
+        {2, -1, -7},
+        {6, -1,  5}
+    };
+
+    REQUIRE(a.minor(0, 0) == -12.0);
+    REQUIRE(a.cofactor(0, 0) == -12.0);
+    REQUIRE(a.minor(1, 0) == 25.0);
+    REQUIRE(a.cofactor(1, 0) == -25.0);
+}