Answer:
25 degrees
Explanation:
There are 2 unknown angles in the triangle
Since the blank angle is next to 76 on a straight line it is a supplementary angle so I just subtract 76 from 180
180-76
104
Now we know 2 angles inside the triangle and we know all 3 angles added together equals `180 so we just subtract the 2 angles from 180
180-104= 76
76-51 = 25
x = 25 degrees
Hope this helps