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Find the type of triangle from the given sides
• Last Updated : 29 Sep, 2020

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 = 3
Output: Obtuse-angled Triangle
Explanation:
Triangle with the sides 1, 2 and 3 is an obtuse-angled triangle

Input: A = 2, B = 2, C = 2
Output: Acute-angled Triangle
Explanation:
Triangle with the sides 2, 2, and 2 is an acute-angled triangle

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

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 using namespace std;  // Function to find the type of// triangle with the help of sidesvoid 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 Codeint 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 sidesimport java.util.*;  class GFG{  // Function to find the type of// triangle with the help of sidesstatic 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 sidesdef 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 Codeif __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 sidesusing System;  class GFG{   // Function to find the type of// triangle with the help of sidesstatic 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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