Answer:
63
Step-by-step explanation:
Because the two labelled angles make up a line, we know their sum is 180.
So, add them and set them equal to 180:
2x + (x - 9) = 180
Combine like terms:
3x - 9 = 180
3x = 189
x = 63
Thus, the answer is 63.
~ an aesthetics lover
