Help with paragraph proofs

Given: 1 and 2 are supplementary, and 2 and 3 are supplementary.

Prove:1 is equal to 3

By the definition of supplementary angles, m1 + m2 = ______ (a) and m2 + m3 = ______ (b). Then m1 + m2 = m2 + m3 ______ (c). Subtract m2 from each side. You get m1 = _______ (d), or 1 _________ (e).

Please help! Any help will be appreciated.

m1+m2=180
m2+m3=180
m1+m2=m2+m3=180
subtract m2 from each side.
m1=m3 or 1=m3/m1