Geometric proofs can be written in one of two ways: two columns, or a
paragraph. A paragraph proof is only a two-column proof written in
sentences. However, since it is easier to leave steps out when writing a
paragraph proof, we'll learn the two-column method.
A two-column geometric proof consists of a list of
statements, and the reasons that we know
those statements are true. The statements are listed in a column on the left,
and the reasons for which the statements can be made are listed in the right
column. Every step of the proof (that is, every conclusion that is made) is a
row in the two-column proof.
