Answer:
x = 15 degrees.
Step-by-step explanation:
m < CBA = 180 - 9x (Adjacent angles).
By the External Angle of a Triangle theorem:
8x = 5x + (180-9x)
8x = 5x - 9x + 180
8x = -4x + 180
12x = 180
x = 15.
15
(180-8x)+5x+(180-9x)=180
360-360-8x+5x-9x=180-360
-12x/-12=-180/-12
x=15
