- Write a C program find third angle of triangle.

#### Required Knowledge

We will first take two angles of a triangle as input from user using scanf function. To find the **third angle of triangle** we will use below mentioned angle sum property of a triangle.

Sum of all internal angles of a triangle is 180 degrees.

**A + B + C = 180**

## C program to find third angle of a triangle

/* * Given two angles of a triangle, Here is the * C program to find third angle */ #include <stdio.h> #define ANGLE_SUM 180 int main() { /* Three angles of a triangle */ float a1, a2, a3; /* * Take two angles as input from user */ printf("Enter Two Angles of a Triangle\n"); scanf("%f %f", &a1, &a2); /* Sum of all three angles of a triangle is 180 degrees */ a3 = ANGLE_SUM - (a1 + a2); printf("Third Angle = %0.4f", a3); return 0; }

Output

Enter Two Angles of a Triangle 30 60 Third Angle = 90.0000

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