**Step 1:**First of all we will determine all variables present in the expression. For Example: If we have two variables then we require two expressions to get the value of variables.

**Step 2:**Now rearrange the expressions by separating constant terms and variables.

**Step 3:**If there is more than one variable in an expression then we will use substitution method. We will substitute the value

of one variable in terms of another variable. We basically use substitution method to reduce an expression in simpler form.

**Step 4:**Now we will resolve the expression. We will apply basic mathematical operations on expression such as addition, subtraction, multiplication and division. After applying the operation we will get the value of variable in expression.

**Step 5:**Now place the value of the variable in the expression to get the value of expression.

Let us take an example to understand this concept. Assume that we have an expression x - 5 = 8. Here we have to find the value of expression.

First of all we determine the number of variables in the expression. Here only one variable is present in the expression. We will separate the constant terms and variables in expression.

x = 8 + 5

Now we will perform basic mathematical operations like addition and subtraction.

x = 8 + 5,

x = 13,

So value of variable x = 13 and expression value is:

13 – 5 = 8,

8 = 8.