CONCEPT OF EQUATION - LHS, RHS
Concept of equation can be understood easily by taking an example. You are given that, your age is exactly half of your father's age, and the sum of your age and your father age is equal to 60, then find out your age and your father's age.
In this example, you are going to equate two values and they are sum of the ages = 60,
On the left hand side, you are going to write as, (X/2)+X=60,
...