I made this with a lot of heart, and every purchase helps me keep creating.
If you like what I do or just want to support independent makers, check it out:
http://amazon.com/gp/product/B093D22DGN
Thank you for being here—it really means a lot.
Learn this proposition with interactive step-by-step here:
coming soon
Playlist of Euclid's Elements in link below:
http://www.youtube.com/playlist?list=PLFC65BA76F7142E9D
In proposition 4, we prove that two triangles are congruent if they share a corresponding side, angle, and side.
