In Adobe Illustrator, drawing an arc involves either filling in a dialog box called Arc Segment Tool Options, or clicking and dragging around on the screen to try to get something like what you want. If you want anything other than a quarter circle (90°), you have to draw it first, and then edit the endpoints.
I think there's a better way. You can try my approach out here:
The basic idea is that you first set the two endpoints, and then move the mouse around to balloon the arc to the right size.
So which method to you like?
8 hours ago