(Taken from a source)
Simplifying
3z + 9 = 0
Reorder the terms:
9 + 3z = 0
Solving
9 + 3z = 0
Solving for variable 'z'.
Move all terms containing z to the left, all other terms to the right.
Add '-9' to each side of the equation.
9 + -9 + 3z = 0 + -9
Combine like terms: 9 + -9 = 0
0 + 3z = 0 + -9
3z = 0 + -9
Combine like terms: 0 + -9 = -9
3z = -9
Divide each side by '3'.
z = -3
Simplifying
z = -3
Hope this helped!
:)