Note: If we divide an expression or number by 2, it’ll return only the integer part and the decimal part will be discarded. So we are dividing the expression by 2.0 (which is of type double).
printf("Enter height and width of a right angled triangle\n");
scanf("%f%f", &h, &w);
area = (h * w) / 2.0;
printf("Area of a Right Angled Triangle is %f\n", area);
return 0;
}
#include < stdio.h >
int main()
{
float h, w, area;
printf("Enter height and width of a right angled triangle\n");
scanf("%f%f", &h, &w);
area = (h * w) / 2.0;
printf("Area of a Right Angled Triangle is %f\n", area);
return 0;
}
Output: Enter height and width of a right angled triangle 10 5 Area of a Right Angled Triangle is 25.000000
Validate the Input and Find Area of Triangle: C Program
Formula To Calculate Area of Triangle when its Base and Height are given
Area = (Base * Height) / 2.0;
Note: If we divide an expression or number by 2, it’ll return only the integer part and the decimal part will be discarded. So we are dividing the expression by 2.0 (which is of type double).
Find Area of a Triangle Using Its Base and Height: C Program
#include < stdio.h >
int main()
{
float base, height, area;
printf("Enter length of base of Triangle\n");
scanf("%f", &base);
printf("Enter length of height of Triangle\n");
scanf("%f", &height);
area = (base * height) / 2.0;
printf("Area of Triangle is %0.2f\n", area);
return 0;
}
Output: Enter length of base of Triangle 15 Enter length of height of Triangle 25 Area of Triangle is 187.50
Validate the Input and Find Area of Triangle: C Program
#include < stdio.h >
int main()
{
float base, height, area;
printf("Enter length of base of Triangle\n");
scanf("%f", &base);
printf("Enter length of height of Triangle\n");
scanf("%f", &height);
if(base == 0 || height == 0)
{
printf("Invalid Input\n");
}
else
{
area = (base * height) / 2.0;
printf("Area of Triangle is %0.2f\n", area);
}
return 0;
}
Output 1: Enter length of base of Triangle 0 Enter length of height of Triangle 25 Invalid Input
Output 2: Enter length of base of Triangle 15 Enter length of height of Triangle 30 Area of Triangle is 225.00
Note: Note that the area of Triangle has only 2 digits after the decimal point. That is because we have %0.2f as format specifier in the printf method where we are printing out the area of Triangle.
Three angles of a Triangle are entered through the keyboard, write a C program to check whether the Triangle is valid or not. The Triangle is valid if the sum of all the angles is exactly equal to 180.
We ask the user to enter all 3 angles of a Triangle. Then we add all these angles and if the result is 180 then its a valid Triangle, if not, its not a valid Triangle.
Formula To Calculate Valid Triangle a + b + c = 180;
where a, b and c are 3 angles of a Triangle.
Note: Also not that if any of the angle is 0, then those 3 angles can’t form a Triangle, so it’s a invalid Triangle.
If the three sides of a Triangle are entered through the keyboard, write a program to check whether the Triangle is isosceles, equilateral, scalene Triangle.
Note: Equilateral Triangle: A Triangle is called equilateral triangle if length of 3 sides of it are equal. Example: a = 10, b = 10, c = 10;
Isosceles Triangle: A Triangle is called isosceles triangle if length of 2 sides of it are equal. Example: a = 5, b = 10, c = 10;
Scalene Triangle: A Triangle is called scalene triangle if length of all 3 sides are different or not equal. Example: a = 5, b = 6, c = 10;
C Program To Check whether a Triangle is Equilateral, Isosceles or Scalene
#include < stdio.h >
int main()
{
float a, b, c, flag = 0;
printf("Enter values for a, b and c\n");
scanf("%f%f%f", &a, &b, &c);
if(a == b && b == c)
{
printf("It's an Equilateral Triangle\n");
}
else if(a == b || a == c || b == c)
{
printf("It's an Isosceles Triangle\n");
}
else
{
printf("It's a Scalene Triangle\n");
}
return 0;
}
Output 1: Enter values for a, b and c 10 10 10 It’s an Equilateral Triangle
Output 2: Enter values for a, b and c 20 20 30 It’s an Isosceles Triangle
Output 3: Enter values for a, b and c 10 15 8 It’s a Scalene Triangle
Here a, b and c are lengths of sides of the triangle. First we check if length of a is equal to length of b and length of c. If that’s true, then its Equilateral Triangle.
Next, if the first condition is false – we check if either length of a is equal to length of b or length of a is equal to length of c or length of b is equal to length of c. If any of these conditions are true, then 2 sides of the Triangle are equal. So its an Isosceles Triangle.
If above two conditions are false, then length of all sides of the Triangle is different or not equal, so it’s a Scalene Triangle.
C Program To Check whether a Triangle is Equilateral, Isosceles or Scalene
First we ask the user to input lengths of 3 sides of the Triangle. We’ll need to write the C program to check if the entered values form a valid Triangle or not. You can find the logic to it at Triangle Valid or Not based On Sides: C Program.
C Program To Check whether a Triangle is Equilateral, Isosceles or Scalene: Valid Triangle
#include < stdio.h >
int main()
{
float a, b, c, flag = 0;
printf("Enter values for a, b and c\n");
scanf("%f%f%f", &a, &b, &c);
if( a>b && a>c)
{
flag = ((b+c) > a);
}
else if( b>c )
{
flag = ((a+c) > b);
}
else
{
flag = ((a+b) > c);
}
if(flag)
{
if(a == b && b == c)
{
printf("It's an Equilateral Triangle\n");
}
else if(a == b || a == c || b == c)
{
printf("It's an Isosceles Triangle\n");
}
else
{
printf("It's a Scalene Triangle\n");
}
}
else
{
printf("Invalid Triangle\n");
}
return 0;
}
Output 1: Enter values for a, b and c 4 5 6 It’s a Scalene Triangle
Output 2: Enter values for a, b and c 30 30 30 It’s an Equilateral Triangle
Output 3: Enter values for a, b and c 10 50 50 It’s an Isosceles Triangle
Output 4: Enter values for a, b and c 10 50 20 Invalid Triangle
Note: Result of output 4 gives “Invalid Triangle” because – the largest side is 50. So the sum of other two sides must be greater than 50. (10+20) = 30. So 30 is not equal to 50, so Triangle can’t be formed with length of sides as 10, 50 and 20.