Answer:
67°
Explanation:
Sum of the interior angles of a triangle = 180
To find x, set the sum of the supplementary angles to the 3 shown angles (x-6, x+9, x) equal to 180:
180 = (180-x+6) + (180-x-9) + (180-x)
180 = 536 - 3x
-357 = -3x
x = 119
119 - 6 = 113 this is the angle supplementary to ∠LMN, therefore:
m∠LMN = 180 - 113 = 67°