Answer:

Step-by-step explanation:
Hello There!
The angle labeled 6x is a right angle
If an angle is formed using the diameter of a circle then the opposite angle of that side is a right angle
So 6x = 90
isolate the variable
divide each side by 6
90/6= 15
6x/6=x
we're left with x = 15
12 is 20% of 60 because 12/60 = 0.2.
Add 8 to both sides
3x=33
Divide both sides by 3
x=11