Answer:
Step-by-step explanation:
Find a similar diagram attached
Let the exterior angle be 155°
The sum of interior angle is equal to the sum of the exterior angle of the triangle
Interior angle are angles inside the triangles
Sum of interior angles = 90 + x
Exterior angles are those outside the triangle.
Exterior angle = 155°
Since sum of interior = exterior, hence;
90 + x = 155
x = 155 - 90
x = 65°
Hence the value of x is 65°
Note that the same concept can be used for any other triangle extending to form an exterior angle