Answer:
21.6 degrees
Step-by-step explanation:
the sum of angles in a triangle is 180 degrees
71 + x + (4x-11) = 180
open the brackets
71 + x +4x - 1 = 180
71 + 1 + x + 4x =180
72 + 5x =180
5x = 180 -72
5x = 108
x = 108/5 = 21.6
