The measure of the angle indicated is 41 degrees
In order to determine the measure of the unknown angle, we must know that the sum of angles in the given triangle is 180 degrees.
Determine the vertex angle at the centre.
y = 180 - (60 + 55)
y = 180 - 115
y = 65
Determine the unknown angle ?
? + y + 74 = 180
? + 65 + 74 = 180
? = 180 - 139
? = 41 degrees
Hence the measure of the angle indicated is 41 degrees