Answer:
The dimensions must all add up to 180°.
Explanation:
For example;
Your triangles' angles are: 56, 77, and 47.
56 + 77 + 47 = 180
*You did not give me any values to solve for, but just since you didn't- I'v provided an example to assist you in doing it yourself. If you want me to solve your full equation please add the angles or 3 dimensions of the triangle.
I hope this helped!