My program is having slight precision errors

Question

So I'm trying to program a way to solve linear equations in java but when doing math like 24.4-11.6 it has an error where it outputs 12.79 instead of 12.8 here's the code I got, I tried to work around the issue by converting the number to an int by multiplying it by 10000 and the doing the math, after which i divide it by 10000 but in the RtChngX method it seems to be outputting 0 :

import java.util.Scanner;

public class x_y_intercept_with_2_coords {

    public static void main(String[] args) {
  
    System.out.println("yinter or xinter");
    Scanner scanner = new Scanner(System.in);
    String interCheck = scanner.nextLine();
    
    
    if(interCheck.equals("yinter")) {
    float[] a = new float[2];
    float[] b = new float[2];
    System.out.println("first x coord");
    a[0] = scanner.nextFloat();
    System.out.println("second x coord");
    a[1] = scanner.nextFloat();
    System.out.println("first y coord");
    b[0] = scanner.nextFloat(); 
    System.out.println("second y coord");
    b[1] = scanner.nextFloat();
    
    backgroundWrkr one = new backgroundWrkr();
    System.out.println("yinter = "+one.bWrkrOne(a, b));
    System.out.println("slope = "+one.getSlope());
    one.rateOfChangeX(a);
    one.rateOfChangeY(b);
        } else {
            float[] a = new float[2];
            float[] b = new float[2];
            System.out.println("first x coord");
            a[0] = scanner.nextFloat();
            System.out.println("second x coord");
            a[1] = scanner.nextFloat();
            System.out.println("first y coord");
            b[0] = scanner.nextFloat(); 
            System.out.println("second y coord");
            b[1] = scanner.nextFloat();
            
            backgroundWrkr one = new backgroundWrkr();
            System.out.println("xinter = "+one.bWrkrTwo(a, b));
            System.out.println("slope = "+one.getSlope());
        }
    }

public class backgroundWrkr {

    float slope;
    float rtChngX;
    float rtChngY;
        backgroundWrkr(){
            
        }
        public float bWrkrOne(float[] a, float[] b) {
            float xslope = a[1]-a[0];
            float yslope = b[1]-b[0];
            slope = yslope/xslope;
            float yinter = b[0]-slope*a[0];
            return yinter;
            
        }
          
        public float bWrkrTwo(float a[], float b[]) {
            float xslope = a[1]-a[0];
            float yslope = b[1]-b[0];
            slope = yslope/xslope;
            float yinter = b[0]-slope*a[0];
            float xinter = yinter*-1/slope;
            
            return xinter;
            
        }
        
        public float getSlope() {
            return slope;
        }
        public void rateOfChangeX(float a[]) {
        float gaeA = a[1]*1000;
        System.out.println(gaeA);
        float gaeB = a[0]*1000;
        System.out.println(gaeB);
        int GaeA = (int)gaeA;
        System.out.println(GaeA);
        int GaeB = (int)gaeB;
        System.out.println(GaeB);
        float temp = GaeA-GaeB;
        System.out.println(temp);
        rtChngY = temp/1000;
        System.out.println("rtChngX = "+rtChngX);   
        }
        public void rateOfChangeY(float b[]) {
        float gaeA = b[1]*10000;
        float gaeB = b[0]*10000;
        int GaeA = (int)gaeA;
        int GaeB = (int)gaeB;
        int temp = GaeA-GaeB;
        rtChngY = temp/10000;
        System.out.println("rtChngY = "+rtChngY);   
    }
    
            
}