This one is fairly straight forward!
Enter coordinate values between \(-99\) and \(999\) and click "Plot Line!" or the Enter key.
I recommend that you keep to two digit numbers to stop things getting messy.
Next you should try and work out the line equation and midpoint yourself, then click the corresponding buttons to reveal the answers.
The "Perpendicular at M" button will both draw the perpendicular line through the midpoint, and show the equation of the line underneath.
If you find any problems or have ideas for improvements, contact by Twitter: @NextLevelMaths.