How do you solve \[-18=3x-9\]?

Hint: In this problem, we have to solve and find the value of x. we can first take the constant term -9, from the right-hand side to the left-hand side, so that the given problem will be easier to solve as we can have the terms with variables to be simplified in one side and the constant on the other side. We can then simplify the equation to get the value of x.

Complete step by step solution:
We know that the given equation to be solved is,
 \[-18=3x-9\]
We can now add the number 9 on both the left-hand side and the right-hand side of the equation, we get
\[-18+9=3x-9+9\]
We can now cancel the similar terms in the above step, we get
\[\Rightarrow -9=3x\]
We can now simplify the above step by dividing 3 on both sides, the terms with same variables in the right-hand side, we get
\[\Rightarrow x=-3\]
Therefore, the value of $x$ is $-3$.

Note:
Students make mistakes while adding or subtracting the correct numbers to the given equation on both the left-hand side and the right-hand side of the equation in order to cancel similar terms to get a simplified form so that we can find the value of the given unknown variable in the given equation. We can substitute the resulting value in the equation to check for the correct values.
We can substitute x = -3 in \[-18=3x-9\],
\[\begin{align}
  & \Rightarrow -18=3\left( -3 \right)-9 \\
 & \Rightarrow -18=-9-9 \\
\end{align}\]
Therefore, the values are correct.