• Type the x and y coordinates for point A to change the angle <AOC.
• Type the x and y coordinates for point B to change the angle <BOD.
• Keep the horizontal (x) values between 0 and 60 (if you want to see it!)
• Keep the veritical (y) values between -20 and +20
• Press the "Redraw" button after you type the new coords of A and/or B.
• Check the "Measure minor" box to measure the shortest path (0°-180°).

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