I have been asked to do a two column proof for a trapezoid. I am stumped on what to do. I am homeschooled and I am using a tough curriculum so the book I have for geometry assumes you know how to do everything or figure it out on your own. I would really appriciate some help please!!

figure,

question: Given: ROSE is a trapezoid with bases OS and RE.

Prove, OI • RI = EI • SI

and this is supposed to be a two column proof.

Thank you very very much!!