How to draw a polygon, then resize it by scale and move it to center of display area?

Question

I was doing my homework on Graphics2d and Polygon, however I am not able to search (or maybe using wrong keyword?) the solution of my homework.

Hoemwork question screenshot:

The code below is the first approach I have tried, I only see empty screen. After some searching on Google, I realized I got wrong usage of .scale and .translate, so I move it before the .drawPolygon, this time I can see the polygon, but it is after I enlarge my window, which means it is not visible within the 300, 300 initially?

import javax.swing.*;
public class PolygonExample extends JFrame{
    public PolygonExample(){
        super("Drawing Red Polygon");
        setSize(300, 300);
        setVisible (true);
    }
    public void paint (Graphics g){
        super.paint(g);
        int xValue[] = {0, 10, 7, -7, -10};
        int yValue[] = {-10, -2, 10, 10, -2};
        Polygon polygon = new Polygon(xValue, yValue, 5);
        g.setColor(Color.RED);
        g.drawPolygon(polygon);

        Graphics2D g2d = (Graphics2D) g;
        g2d.scale(5.0, 5.0);
        g2d.translate(150, 150);
    }
    public static void main(String[] args) {
        new PolygonExample();
    }
}

I expect the polygon would be drawn on the center of the display area (within 300x300), but I didn't see anything on the screen. After enlarge window, I can see my polygon but it is not within the 300, 300 area I have set

Answer 1

import javax.swing.*;
import java.awt.geom.AffineTransform;
public class PolygonExample extends JFrame{
    public PolygonExample(){
        super("Drawing Red Polygon");
        setSize(300, 300);
        setVisible (true);
    }
    public void paint (Graphics g){
        super.paint(g);
        int xValue[] = {0, 10, 7, -7, -10};
        int yValue[] = {-10, -2, 10, 10, -2};
        Polygon polygon = new Polygon(xValue, yValue, 5);

        g.setColor(Color.RED);
        Graphics2D g2d = (Graphics2D) g;
        AffineTransform at = new AffineTransform(5., 0., 0., 5., 150., 150.);
        g2d.setTransform(at);

        g.drawPolygon(polygon);     
    }
    public static void main(String[] args) {
        new PolygonExample();
    }
}

The code above done what I wanted to do

Thanks @MadProgrammer for the resource