Given three integers **A**, **B**, and **C** which denotes the sides of a triangle, the task is to check that the triangle is a right-angled, acute-angled or obtuse-angled triangle.

**Examples:**

Input:A = 1, B = 4, C = 3Output:Obtuse-angled TriangleExplanation:

Triangle with the sides 1, 2 and 3 is an obtuse-angled triangle

Input:A = 2, B = 2, C = 2Output:Acute-angled TriangleExplanation:

Triangle with the sides 2, 2, and 2 is an acute-angled triangle

**Approach:** The idea is to use the facts from the cosine law to check the type of triangle using this formulae –

It generalizes the Pythagorean Theorum, which states that for a right-angled triangle square of the hypotenuse is equal to the sum of squares of the base and height of the triangle, which is

Similarly, It can be observed that

For acute-angled triangle

For Obtuse-angled triangle

Below is the implementation of the above approach:

## C++

`// C++ implementation to find` `// the type of triangle with` `// the help of the sides` ` ` `#include <bits/stdc++.h>` `using` `namespace` `std;` ` ` `// Function to find the type of` `// triangle with the help of sides` `void` `checkTypeOfTriangle(` `int` `a, ` ` ` `int` `b, ` `int` `c){` ` ` `int` `sqa = ` `pow` `(a, 2);` ` ` `int` `sqb = ` `pow` `(b, 2);` ` ` `int` `sqc = ` `pow` `(c, 2);` ` ` ` ` `if` `(sqa == sqb + sqc || ` ` ` `sqb == sqc + sqa || ` ` ` `sqc == sqa + sqb){` ` ` `cout << ` `"Right-angled Triangle"` `;` ` ` `}` ` ` `else` `if` `(sqa > sqc + sqb ||` ` ` `sqb > sqa + sqc ||` ` ` `sqc > sqa + sqb){` ` ` `cout << ` `"Obtuse-angled Triangle"` `;` ` ` `}` ` ` `else` `{` ` ` `cout << ` `"Acute-angled Triangle"` `;` ` ` `}` `}` ` ` `// Driver Code` `int` `main()` `{` ` ` `int` `a, b, c;` ` ` `a = 2;` ` ` `b = 2; ` ` ` `c = 2;` ` ` ` ` `// Function Call` ` ` `checkTypeOfTriangle(a, b, c);` ` ` `return` `0;` `}` |

## Java

`// Java implementation to find` `// the type of triangle with` `// the help of the sides` `import` `java.util.*;` ` ` `class` `GFG` `{` ` ` `// Function to find the type of` `// triangle with the help of sides` `static` `void` `checkTypeOfTriangle(` `int` `a, ` ` ` `int` `b, ` `int` `c){` ` ` `int` `sqa = (` `int` `)Math.pow(a, ` `2` `);` ` ` `int` `sqb = (` `int` `)Math.pow(b, ` `2` `);` ` ` `int` `sqc = (` `int` `)Math.pow(c, ` `2` `);` ` ` ` ` `if` `(sqa == sqa + sqb || ` ` ` `sqb == sqa + sqc || ` ` ` `sqc == sqa + sqb){` ` ` `System.out.print(` `"Right-angled Triangle"` `);` ` ` `}` ` ` `else` `if` `(sqa > sqc + sqb ||` ` ` `sqb > sqa + sqc ||` ` ` `sqc > sqa + sqb){` ` ` `System.out.print(` `"Obtuse-angled Triangle"` `);` ` ` `}` ` ` `else` `{` ` ` `System.out.print( ` `"Acute-angled Triangle"` `);` ` ` `}` `}` ` ` `// Driver Code ` `public` `static` `void` `main (String []args)` `{` ` ` `int` `a, b, c;` ` ` `a = ` `2` `;` ` ` `b = ` `2` `; ` ` ` `c = ` `2` `;` ` ` ` ` `// Function Call` ` ` `checkTypeOfTriangle(a, b, c);` `}` `}` ` ` `// This code is contribute by chitranayal` |

## Python3

`# Python3 implementation to find` `# the type of triangle with` `# the help of the sides` ` ` `# Function to find the type of` `# triangle with the help of sides` `def` `checkTypeOfTriangle(a,b,c):` ` ` `sqa ` `=` `pow` `(a, ` `2` `)` ` ` `sqb ` `=` `pow` `(b, ` `2` `)` ` ` `sqc ` `=` `pow` `(c, ` `2` `)` ` ` ` ` `if` `(sqa ` `=` `=` `sqa ` `+` `sqb ` `or` ` ` `sqb ` `=` `=` `sqa ` `+` `sqc ` `or` ` ` `sqc ` `=` `=` `sqa ` `+` `sqb):` ` ` `print` `(` `"Right-angled Triangle"` `)` ` ` ` ` `elif` `(sqa > sqc ` `+` `sqb ` `or` ` ` `sqb > sqa ` `+` `sqc ` `or` ` ` `sqc > sqa ` `+` `sqb):` ` ` `print` `(` `"Obtuse-angled Triangle"` `)` ` ` ` ` `else` `:` ` ` `print` `(` `"Acute-angled Triangle"` `)` ` ` `# Driver Code` `if` `__name__ ` `=` `=` `'__main__'` `:` ` ` `a ` `=` `2` ` ` `b ` `=` `2` ` ` `c ` `=` `2` ` ` ` ` `# Function Call` ` ` `checkTypeOfTriangle(a, b, c)` ` ` `# This code is contributed by mohit kumar 29` |

## C#

`// C# implementation to find` `// the type of triangle with` `// the help of the sides` `using` `System;` ` ` `class` `GFG` `{` ` ` `// Function to find the type of` `// triangle with the help of sides` `static` `void` `checkTypeOfTriangle(` `int` `a, ` ` ` `int` `b, ` `int` `c){` ` ` `int` `sqa = (` `int` `)Math.Pow(a, 2);` ` ` `int` `sqb = (` `int` `)Math.Pow(b, 2);` ` ` `int` `sqc = (` `int` `)Math.Pow(c, 2);` ` ` ` ` `if` `(sqa == sqa + sqb || ` ` ` `sqb == sqa + sqc || ` ` ` `sqc == sqa + sqb){` ` ` `Console.Write(` `"Right-angled Triangle"` `);` ` ` `}` ` ` `else` `if` `(sqa > sqc + sqb ||` ` ` `sqb > sqa + sqc ||` ` ` `sqc > sqa + sqb){` ` ` `Console.Write(` `"Obtuse-angled Triangle"` `);` ` ` `}` ` ` `else` `{` ` ` `Console.Write( ` `"Acute-angled Triangle"` `);` ` ` `}` `}` ` ` `// Driver Code ` `public` `static` `void` `Main(String []args)` `{` ` ` `int` `a, b, c;` ` ` `a = 2;` ` ` `b = 2; ` ` ` `c = 2;` ` ` ` ` `// Function Call` ` ` `checkTypeOfTriangle(a, b, c);` `}` `}` ` ` `// This code is contributed by 29AjayKumar` |

**Output:**

Acute-angled Triangle

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