Answer:
Using exterior angle theorem, we can find the answer.
x+45+3x = 6x+5
4x+45 = 6x+5
45 = 2x+5
40 = 2x
x = 20
TO FIND <ABC, WE WILL NEED TO FIRST FIND THE EXTERIOR ANGLE.
6x+5
= 6(20)+5
= 120+5
= 125
m<ABC:
180-125 (REASON: linear pair)
= 55
