Answer:
Step-by-step explanation:
(-16x+13)+(-20x+23)=180. I know that the sum of those two angles would equal 180, since they are supp.
x=-4
Then I would sub in -4 where I see a x
-16(-4)+13=77
-20(-4)+23=103
angle LMP = 77
angle NMP = 103
together = 180 so it's correct
