Answer:
The answer would be D.
Explanation:
If x= 28, then you get 50 right off the bat, then you have 2x and 3x - 10 left.
2 x 28 = 56, and 3 x 28 - 10 = 74.
50 + 74 = 124, and 124 + 56 = 180.
A triangles sides must equal 180 when all added together, so the correct answer is D.