Update README.md

Signed-off-by: Fabiana 🚀  Campanari <113218619+FabianaCampanari@users.noreply.github.com>

Author: FabianaCampanari

README.md

@@ -286,8 +286,11 @@ The **graphical method** for solving simple linear programming (LP) problems inv
  <br>
 
 5. **Determine the Optimal Solution:**
-   - For a [**maximization**]() problem, the vertex that yields the **largest** value of the objective function is the optimal solution.
-   - For a [**minimization**]() problem, the vertex that yields the **smallest** value of the objective function is the optimal solutio
+   - For a **maximization** problem, the vertex that yields the **largest** value of the objective function is the optimal solution [1, 6].
+     
+   -  For a **minimization** problem, the vertex that yields the **smallest** value of the objective function is the optimal solution [2, 7].
+  
+