Answer:
D
Explanation:
This is a triangle, which means that all angles need to add up to 180. We can then add up the expressions, set them equal to 180, and solve for y:
y + (y - 12) + 56 = 180
2y - 12 + 56 = 180
2y + 44 = 180
2y = 136
y = 68
The answer is D.