diff --git a/src/TriangleChecker.java b/src/TriangleChecker.java
index 14f4841..672ae52 100644
--- a/src/TriangleChecker.java
+++ b/src/TriangleChecker.java
@@ -1,9 +1,9 @@
 import java.util.Scanner;
 
 public class TriangleChecker {
-  
+
   public enum TriangleType {
-    NONE, 
+    NONE,
     NORMAL,
     ISOSCELES,  // Gleichschenklig
     EQUILATERAL // Gleichseitig
@@ -32,23 +32,38 @@ public class TriangleChecker {
     switch (type) {
       case NONE:
         System.out.println("Kein Dreieck");
-        break;        
+        break;
       case NORMAL:
         System.out.println("Dreieck");
-        break;        
+        break;
       case ISOSCELES:
         System.out.println("Gleichschenkliges Dreieck");
-        break;        
+        break;
       case EQUILATERAL:
         System.out.println("Gleichseitiges Dreieck");
-        break;        
+        break;
     }
   }
 
   // Analyse der Dreiecksart
   public static TriangleType checkTriangle(float a, float b, float c) {
+
+    if (checkTriangleShape(a, b, c)) {
+      if (a == b && a == c) return TriangleType.EQUILATERAL;
+      if (a == b || a == c || b == c)
+        return TriangleType.ISOSCELES;
+      return TriangleType.NORMAL;
+    }
+
     return TriangleType.NONE;
   }
 
+  public static boolean checkTriangleShape(float a, float b, float c) {
+
+    if (a <= 0 || b <= 0 || c <= 0)
+      return false;
+    return a + b > c && a + c > b && b + c > a;
+
+  }
 
 }
\ No newline at end of file
diff --git a/test/TriangleCheckerTest.java b/test/TriangleCheckerTest.java
index 5c9ff57..4336d6e 100644
--- a/test/TriangleCheckerTest.java
+++ b/test/TriangleCheckerTest.java
@@ -2,7 +2,7 @@ import org.junit.Test;
 import static org.junit.Assert.*;
 
 public class TriangleCheckerTest {
-    
+
     @Test
     public void testValidTriangle() {
 
@@ -10,12 +10,40 @@ public class TriangleCheckerTest {
         float a = 2;
         float b = 3;
         float c = 4;
+        float d = 32;
+        float e = 8;
+        float f = 0;
+        float g = 6;
+        float h = 9;
+        float i = 28;
 
         // Act
-        TriangleChecker.TriangleType type = TriangleChecker.checkTriangle(a, b, c);
+        TriangleChecker.TriangleType normal = TriangleChecker.TriangleType.NORMAL;
+        TriangleChecker.TriangleType none = TriangleChecker.TriangleType.NONE;
+        TriangleChecker.TriangleType isoceles = TriangleChecker.TriangleType.ISOSCELES;
+        TriangleChecker.TriangleType equilateral = TriangleChecker.TriangleType.EQUILATERAL;
+
+        assertTrue(TriangleChecker.checkTriangleShape(a, b, c));
+        assertFalse(TriangleChecker.checkTriangleShape(a, d, c));
+        assertFalse(TriangleChecker.checkTriangleShape(e, d, e));
+        assertFalse(TriangleChecker.checkTriangleShape(a, f, h));
+        assertFalse(TriangleChecker.checkTriangleShape(i, c, d));
+        assertTrue(TriangleChecker.checkTriangleShape(g, i, d));
 
         // Assert
-        assertEquals(TriangleChecker.TriangleType.NORMAL, type);
+        assertEquals(normal, testTriangle(a, b, c));
+        assertEquals(none, testTriangle(a, b, d));
+        assertEquals(none, testTriangle(a, f, d));
+        assertEquals(none, testTriangle(f, f, d));
+        assertEquals(none, testTriangle(c, c, d));
+        assertEquals(equilateral, testTriangle(a, a, a));
+        assertEquals(isoceles, testTriangle(a, d, d));
+
+    }
+
+    public TriangleChecker.TriangleType testTriangle(float side1, float side2, float side3) {
+
+        return TriangleChecker.checkTriangle(side1, side2, side3);
 
     }