what is geogebra
I have a copy of GeoGebra that I downloaded completely for free.
I do my co-ordinate geometry graphing on Desmos
I draw all my euclidean geometry diagrams using GeoGebra. It is well worth learning.
Geogebra is a piece of software that is commonly used to help students manipulate visual geometry problems. You should be able to find a free trial online.
Here's the GeoGebra website: http://www.geogebra.org/cms/en/
Here's another graphing site I like.....Desmos Grapher....easy to use.........https://www.desmos.com/calculator
(Nothing to download with Desmos!!!)