1.) Go to this link: http://www.geogebra.org/cms/en/download/
2.) Download one of the versions of Geogebra that will work for you
3.) Save it to your desktop
4.) Open up the application, a graph will pop up
5.) In the input window at the bottem, type in y=x^2+2x+3, hit enter
6.) In the input window at the bottem, type in y=2x+3
7.) Notice that the equations have been graphed for you and the equations are shown in the upper left hand corner, mine are labeled c and a.
8.) Since mine are labeled c and a, I will now type in intersect[a,c], and hit enter, it will tell you where lines a and c intersect. It labels this point A, and tells me its (0.3.
9.) Now I can click the "ABC" Button above and write a text not "Intersection Point" on the graph.
10.) Go to file and export, you can export this graph as a picture and save it to your desktop. This picture can then be dragged into your assignments!