ImageMagick, PHP, and Lines

[Anon]

I'm trying to use PHP along with ImageMagick to do some drawing.

So far I have been able to use the system() command to execute the following ImageMagick code:
convert -size 500x500 -pen white -stroke green -draw "Circle +250+250 +1+251" XC:white sample321.gif

I would like to know how I can add a line to that (with either one command or more) that connects points 0,250 and 500,250.

Thanks alot.

Also - Is it possible to draw lines at 10 degree angles from the middle of the circle (There's 360 degrees in a circle, so there would be 36 lines)?