Answer:
Step-by-step explanation:
Isolate the term of x from one side of the equation.
First, add by 9 from both sides.
x-9+9=-21+9
Solve.
-21+9=-12
X=-12
Switch sides.
x+10=112
Subtract by 10 from both sides.
x+10-10=112-10
Solve.
112-10=102
X=102
Switch sides.
x-30=14
Add by 30 from both sides.
x-30+30=14+30
Solve.
x=44
Switch sides.
x-12=3
Add by 12 from both sides.
x-12+12=3+12
Solve.
Add the numbers from left to right.
3+12=15
x=15
I hope this helps you! Let me know if my answer is wrong or not.