Answer:
x=10
Explanation:
we know that it is a straight line and if we add it up then it will be 180 degrees. So first we add them both up together
8x + 14 + 9x - 4 = 17x + 10 = 180
Then you want to separate the X's and the numbers
in this case you subtract 10 on both sides to get rid of the number on the left side so there is only X
17x+10=180
-10 -10
17x=170
than simplify
17x=170
/17 /17
x=10