This is another applet which allows you to play around with equations. This time they are harder.
Every time you click "New Problem" a new equation appears for you to solve. There are fourteen levels of difficulty (!), and you can choose which one you want to try from the drop-down menu at the top right.
There are 4 sliders at the bottom of the page, and each allows you to do something to the equation.
1 - Add or take away x's  
2 - Add or take away numbers.
3 - Multiply by a number.  
4 - Divide by a number.
There are also some buttons along the bottom. You should experiment with these to see what effect they have, if any.

To solve the equation you have to do the right things in the right order. You have finished when you see ' x = ' and some number on the right.
As you drag a slider left and right, you'll see some writing appear on the screen. This tells you what will happen when you release the slider. In other words, you must decide what you want to do, drag the slider to correct position, and then release it. You will then see the equation change.
Play around. Don't worry if at first you make a bit of a mess. You can always go back to the start by pressing "Start again".
Good luck, and don't let anybody tell you that you can't do algebra!