- One of the expressions must have a variable.
- LHS of the equation is equal to the RHS of the equation.
- An expression does not have equality sign but an equation always has an equality sign.
- If we interchange the position of the expression from LHS to RHS or vice versa, the equation remains the same.
5x + 7 = 2
2 = 5x + 7
Both the above equations are same.