Hey there!
Solve the equation:
x = -15 ✅
9 - 3x = 54
>> Substract 9 from both sides :
9 - 3x - 9 = 54 - 9
-3x = 45
>> Divide each side by -3 :
-3x / -3 = 45 / -3
x = -15
More about equations:
https://brainly.com/question/27436957
Have a good day ;)