**Calculating the area of the triangle** is a common mathematical operation that can easily be implemented in Java. Implementing such operations improves the programming skills of an individual. **Java **is a reputable programming language that provides a platform for implementing these computations with ease. In this article, we will implement and discuss various methods for determining the area of a given triangle in Java.

**How to Find/Calculate the Triangle Area in Java?**

The **area of a triangle** can be computed by taking the product of** base** and **height** and dividing it by **half**. The length of any side of the triangle is the base while the height is calculated as the perpendicular distance of the base and opposite vertex as shown in the figure below:

**Mathematical Formula**

The mathematical formula is as follows:

** ****Area of Triangle = 1/2 * (Base * Height) **

**Implementation in Java **

The two double data type variables “**base**” and “**height**” are initialized with different values. The area of the triangle is determined by taking the product of base and height with **0.5** (½). This result is stored in the variable “**areaTriangle**” which is then printed as output on the console:

```
package areaOfTriangle;
public class areaOfTriangle {
public static void main(String[] args) {
double base = 19.2;
double height = 14.2;
//Two ways of Calculating Triangle
double areaTriangle = 0.5 * ( base * height );
double triangleArea = (base * height ) / 2;
//Printing the area of Triangle using 0.5
System.out.println("Area of triangle is " + areaTriangle); //Printing the area of Triangle using 1/2
System.out.println("Area of triangle is " + triangleArea);}
}
```

**Output **

**How to Calculate the Equilateral Triangle Area in Java?**

Equilateral triangles consist of three sides and each angle is equal in measure. The total of three **interior angles **will give a total of **180 degrees** as shown in the diagram below:

**Mathematical Formula**

The Mathematical equation for calculating the area of an Equilateral triangle is as follows:

** ****Area of an Equilateral Triangle = ****3**** ****/ 4 * ( side) * (side)**

**Implementation in Java**

In the following code, a “**side**” variable of double **data type** is initialized with the respective value. The variable “**b**” stores the result which is returned after calculating the **square root** of **3 **and **dividing** it by **4**. Finally, the variable “**areaTriangle**” stores the product of “**b**” with the square of the “**side**” variable. The print statements display the original and the rounded value of the “**areaTriangle**” variable:

```
package areaOfTriangle;
public class areaOfTriangle {
public static void main(String[] args) {
double side = 14.5;
double b = Math.sqrt(3) / 4;
//Calculating the area
double areaTriangle = b * ( side * side);
//Printing the area of Triangle
System.out.println("Area of triangle is " + areaTriangle );
//roundoff the area
System.out.println("Area of triangle is after rounding off " + Math.round(areaTriangle));
}
}
```

**Output**

**How to Calculate the Isosceles Triangle Area in Java?**

A triangle that has three sides (lengths) equal in measure is known as an **Isosceles** triangle. Similarly, the angles facing the two equal sides are also equal in the isosceles triangle. The total of the three interior angles of the isosceles triangles is 180 degrees.

**Mathematical Formula **

The formula is as follows:

** Area of Isosceles Triangle = 1/4 * base * 4(a*a) – (b*b)**

**Implementation in Java**

In this code, we will calculate the area of the isosceles triangle on the values provided by the user. For this purpose, include the **Scanner class** from the **java.util **package using the following import statement:

```
import java.util .Scanner; //import the Scanner class
```

In the **main()** method, the Scanner object “**input**” is created that accepts the input from the keyboard. The print statement displays the message to the user to enter the length of any two sides of the triangle. The value is then stored in the “**sides**” and “**base**” variables:

```
Scanner input = new Scanner (System.in); //Scanner’s object to read input
System.out.println("Enter the length of two equal sides");
double sides = input.nextDouble();
System.out.println("Enter the base length");
double base = input.nextDouble();
```

The double variable “**isoscelesTriangle**” calculates the area of the isosceles triangle by implementing the formula. The value is then printed on the console:

```
double isoscelesTriangle = (base/4) * Math.sqrt((4 * sides* sides) - (base * base));
System.out.println("Area of Isosceles triangle is "+ isoscelesTriangle);
```

**Complete Code & Output**

**How to Find the Area of the Triangle Using the Heron’s Formula in Java?**

Heron’s formula is practiced when the three lengths of the triangle are mentioned. Another popular name for Heron’s formula is “**Hero Formula**”. To implement the heron’s formula, the measure of the third side of the triangle must not be greater than the sum of the two sides of the triangle. The Mathematical formula is given as follows:

**Area of Triangle = s(s-a) *(s-b) * (s-c)**

Where “**s**” is as calculated by:

**s= (a + b+ c)/ 2**

**Implementation in Java **

The **Scanner class **is imported from the **java.util** package. The object “**input**” of the Scanner class is created inside the **main()** method for reading the user’s input. The print statement displays the message to the user to enter the three values for the sides of the triangle. The values provided are then stored in the variable “**a**”, “**b**” and “**c**”. The **if-statement** checks the condition if the 3rd side of the triangle is less than the total sum of the two sides. The double variable “**s**” stores the sum of three sides which is divided by **2**. By using the **Math.sqrt() **function, Heron’s formula is implemented to calculate the **triangle’s area **when the data given contains **3 lengths **of the triangle. The else block is executed if the “**if**” statement is not true.

```
package areaOfTriangle;
import java.util .Scanner; //importing the scanner class
public class areaOfTriangle {
public static void main(String[] args) // main method to execute the code {
Scanner input = new Scanner (System.in); //creating object of scanner class
//Taking input from the user
System.out.println("Enter the length of three side");
double a = input.nextDouble();
double b = input.nextDouble();
double c= input.nextDouble();
//if the sum of two sides is greater than the third one
if( a+ b > c && a+c > b && b+c > a )
{
double s = (a + b + c)/2;
double areaofTriangle = Math.sqrt(s * ((s - a ) * (s - b ) * ( s- c)));// Calculating the area of triangle using the heron’s formula
System.out.println("Area of Triangle Using the Heron's formula is " + areaofTriangle); //Printing the output
}
else
{
System.out.println("Area of Triangle cannot be calculated");
}
}
}
```

**Output **

**How to Find the Area of a Triangle Using Trigonometry in Java?**

Trigonometry is an essential pillar of Mathematics. We can implement the functions of trigonometry to calculate the area of a triangle in Java using the Math class. The formula for finding the area of a triangle using trigonometry in Java:

Area of Triangle = 1/2 * a * b * sin (Θ)

**Implementation in Java **

The following statement imports the **Scanner class** from the “**java.util**” package. The **Scanner class** provides different methods for taking input from the **user**:

```
import java.util .Scanner;
```

The instance of the Scanner class “**input**” invokes the **nextDouble()** method to read the input from the user. The **angle input** provided by the user is then converted in the radians by the **Math.toRadians()**:

```
Scanner input = new Scanner (System.in);
//Taking user’s input
System.out.println("Enter the length for two side");
double a = input.nextDouble();
double b = input.nextDouble();
System.out.println("Enter the angle ");
double c= input.nextDouble();
//Calculating angle in radians
double angle = Math.toRadians(c);
```

The “**areaofTriangle**” stores the value that is calculated by taking the product of two sides given by the user with the **0.5** (½). The value is then multiplied by the angle’s value returned by the **Math.sin()** method. The output is then printed:

```
/calculate area
double areaofTriangle = 0.5* (a*b) * Math.sin(angle);
System.out.println("Area of Triangle is " + areaofTriangle);
```

**Complete Code & Output**

Here, we will sum up these methods for calculating a triangle’s area in Java.

**Conclusion**

To calculate the area of a triangle, use (**base * height**) / 2, implement **Heron’s formula, **or use the Math class methods etc, as shown in this article. There are several formulas available based on the data given for determining the area of a triangle. For instance, using Heron’s formula when three sides are given, trigonometric functions when the two sides and an angle is given, etc. This article provides a practical implementation of calculating the area for different types of triangles.