Answer:
180=54,6+17,8+x(the third angle)
Explanation:
The three angles in a triangle counted together always give 180 degrees. Therefore, you can use simple equation, in which you subtract the values of the two known angles from 180 (degrees) and the final number will be the value of thethird angle. In this case, it's
180-54,6-17,8=x
107,6=x