Geometry Homework Help on Proofs?

Question

The Supplements of Angle Proof (no picture given)

***NOTE: < is used for the angle symbol (I dont have a way to make an angle symbol)

Given: < 1 is a supplement of < 2
< 3 is a supplement of < 4
m < 2 = m < 4

Prove: m<1=m<3

Statements and Reasons

Answer 1

#1: m∠1 + m∠2 = 180° -- definition of supplement
#2: m∠3 + m∠4 = 180° -- definition of supplement
#3: m∠1 = 180° - m∠2 -- from 1, by simple algebra
#4: m∠3 = 180° - m∠4 -- from 2, by simple algebra
#5: m∠2 = m∠4 -- given
#6: m∠1 = 180° - m∠4 -- from 3 and 5, by substitution property of equality
#7: m∠1 = m∠3 -- from 4 and 6, by transitivity of equality.
#8: Q.E.D. -- from the latin "quod erat demonstrandum," meaning "which was to be demonstrated."