Write a C Program to input two angles from user and find third angle of the triangle. How to find all angles of a triangle if two angles are given by user using C programming. C program to calculate the third angle of a triangle if two angles are given.

**Example**Input

Enter first angle: 60 Enter second angle: 80

**Output**

Third angle = 40

## Required knowledge

Arithmetic operators, Data types, Basic input/output

## Properties of triangle

Sum of angles of a triangle is `180°`.

Let us apply basic math to derive formula for third angle. If two angles of a triangle are given, then third angle of triangle is given by –

## Logic to find third angle of a triangle

Step by step descriptive logic to find third angle of a triangle –

- Input two angles of triangle from user. Store it in some variable say
`a`and`b`. - Compute third angle of triangle using formula
`c = 180 - (a + b)`

. - Print value of third angle i.e. print
`c`.

## Program to find angles of a triangle

```
/**
* C program to find all angles of a triangle if two angles are given
*/
#include <stdio.h>
int main()
{
int a, b, c;
/* Input two angles of the triangle */
printf("Enter two angles of triangle: ");
scanf("%d%d", &a, &b);
/* Compute third angle */
c = 180 - (a + b);
/* Print value of the third angle */
printf("Third angle of the triangle = %d", c);
return 0;
}
```

Output

Enter two angles of triangle: 60 30 Third angle of the triangle = 90

Happy coding 😉

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