4.1. Getting familiar with Geogebra
Find where you can add or remove the axes and the grid, and adjust the view to what is most comfortable for you. Then, carry out the following activities by searching for and using the tools you consider appropriate.
a) Draw any straight line and two others related to it: one parallel and one perpendicular.
b) A non-convex polygon.
c) A regular enneagon.
d) An isosceles triangle.
e) Two externally tangent circles. Two internally tangent circles.