Hello and thanks for stopping by to help me, ive been stumped on this for an hour and a half now. I have this program here :

import java.util.Scanner; import javax.swing.JOptionPane; import java.lang.Math; public class Triangle { double x1 = 0; double x2 = 0; double y1 = 0; double y2 = 0; double z1 = 0; double z2 = 0; double sideA = 0; double sideB = 0; double sideC = 0; double area = 0; double perimeter = 0; double angleA = 0; double angleB = 0; double angleC = 0; public Triangle(int x1, int x2, int y1, int y2, int z1, int z2) { this.x1 = x1; this.x2 = x2; this.y1 = y1; this.y2 = y2; this.z1 = z1; this.z2 = z2; } public double getX1() { return x1; } public double getX2() { return x2; } public double getY1() { return y1; } public double getY2() { return y2; } public double getZ1() { return z1; } public double getZ2() { return z2; } public double getLengthA() { sideA = Math.sqrt(Math.pow((z1-y1)+(z2-y2),2)); return sideA; } public double getLengthB() { sideB = Math.sqrt(Math.pow((z1-x1),2) + Math.pow((z2-x2),2)); return sideB; } public double getLengthC() { sideC = Math.sqrt(Math.pow((y1-x1),2) + Math.pow((y2-x2),2)); return sideC; } public double getHeight() { return z2; } public double getArea() { area = (y1*z2)/2; return area; } public double getPerimeter() { perimeter = getLengthA() + getLengthB() + getLengthC(); return perimeter; } public double getAngleA() { } public double getAngleB() { } public double getAngleC() { } }

This program takes user input and makes some calculations such as area perimeter and angles. Assume the user enter x1=0, x2=0, y1=3, y2=0, z1=3, and z2=4. If a user inputes these numbers when they are callled to do so, all the proper calculations will be made except for angles. I have been stuck on the angle part for an hour and a half trying all different variations of the law of cosines in my code, which is, cos C = (a² + b² - c²)/2ab. I cant get it to work at all though. If anyone could just write it out in code for me for just one of the angels, that would be great, as i could modify it accordingly to find the other ones by myself. Like i said ive been at this for hours and i cant get it to work so its becoming really frustrating. Please help if you can. Thanks!