Answer:
65
Step-by-step explanation:
Exterior angle = Sum of 2 interior angles
x + 31 = x + x - 34
x + 31 = 2x - 34
x - 2x = - 34 - 31
- x = - 65
x = 65
A triangle's angles add up to 180°, and a straight line is 180 degrees, so 180 - x + 31 is the interior angle that isn't labeled.
[tex]x+x-34+180-x-31=180[/tex]
[tex]x=180-115[/tex]
[tex]x=65[/tex]
