Notice:
Unfortunately I’ve never written a two-column proof before. So I can’t do that. Let me know if what I can do helps at all though.
Step-by-step explanation:
A supplementary angle is an angle made up of two angles that have measures that add up to 180°. m∠2 = 45° because 45° added to 135° equals 180°. Therefore making it a supplementary angle. Meaning that m∠2 = 45° is true. Sorry if this doesn’t help. I tried my best.
