How to calculate areas

See more:

Java

Write a program to calculate the area of two geometric shapes: triangles and circles. You must use functions. Here are the functions you should create:
public static double area_triangle( int base, int height ) // returns the area of a triangle
public static double area_circle( int radius ) // returns the area of a circle

Your program should present a menu (triangle or circle) for the user to choose which shape to calculate, then ask them for the appropriate values (length, width, radius, etc.). Then it should pass those values to the appropriate function and display the resulting area.
Notice that you must not input the values inside the functions, and you must not display the values inside the functions. All input and output must be in the main(), and values must be passed to the functions and returned from them.
You'll need the value of π for area_circle(); feel free to use the built-in double variable called Math.PI.

What I have tried:

i tried this and got stuck

import java.util.Scanner;

public class Area {
	

	public static void main(String[] args) {
		public static double area_triangle( int base, int height )  {
			
			System.out.print("Menu");

			
			
			
			
			Scanner input = new Scanner (System.in); 
			base=input.nextInt(); 
			height=input.nextInt(); 
			area_triangle=height*base/2; 
			
			
			
		}
			
	 
	}

}