Check your plotting of polar coordinates and convert to rectangular coordinates.[br][br]A colleague of mine, Tim [url=https://www.geogebra.org/u/tbrzezinski]Brzezinski[/url] has done a lot of different GeoGebra activities. [br][url=https://www.geogebra.org/m/guCcvwFP]https://www.geogebra.org/m/guCcvwFP[/url] is one that helps you see the different names a polar point may have.