Question

Complete the paragraph proof.

Given: <1 and <2 are supplementary, and <2 and <3 are supplementary.
Proof: <1 = <3

By definition of supplementary angles, m<1 + m<2 = ________ and m<2 + m<3 = _______. Then m<1 + m<2 = m<2 + m<3 by the ________. Subtract m<2 from each side. You get m<1 = _____ or <1 = ______

I'm sure the first two is 180 and the last two is m<3 and <3.