The line with y-intercept of 2 is higher than the line with y-intercept of negative-4 that has the same slope.

Short arc LM = 110°

Comment

Any two angles that have their end points on the same end points as a chord and both moving away in the same direction (in this case  down ) are equal. This is a fundamental fact about circles.

Equation

2x + 55 =  x + 55

the only way this is going to make any sense is if x = 0. No other value is possible because it will destroy the equality.

Conclusion

Both angles = 55

But that's not what you are asked for.

What you are asked for

You want to know the measure of arc LM.  

The angle connecting the center of the circle with its two arms running through the end points of the chord = the measure of  arc LM

Draw a dot where the center of the circle is and call it O. Draw in <MOL  

<MOL = 2* either of the 55° = 2 (<LKM)  = 2 * 55 = 110° That's a property of the central angle.

The measure of arc LM = 110°