Answer:
x= -10
Explanation:
So because the angle 55 is part of the same line as one of the unknown angles you can do 180-55 to find that first angle at the top, which is 125.
Next add all three angles (125 + x + 35 + x + 40)=180
Combine the x values to get 2x and subtract the three values from 180
Then 2x= -20, x should be equal to -10
You can plug x back into the values and check your work by adding all the values again, making it all equal to 180 degrees again