how do i work out the angle

Answer:
x = 121°
Step-by-step explanation:
the angle at the vertex = 360° - 304° = 56°
the base angle = 180° - 115° = 65°
The exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.
x is an exterior angle of the triangle , then
x = 56° + 65° = 121°
The angle opposite to 304° has measure:-
The angle aside 115° has measure
Now
Sum of two interiors=Exterior