Answer:
y=180-x is correct and finally y+x=180-46 is also correct
Step-by-step explanation:
Since all triangles add up to 180 degrees(so y+x+46=180 degrees), it cannot be the first one. The second one is correct because of fact families. And the x+y=46 is also incorrect because x+y+46 is 180 not x+y=46.
