 Hi and welcome to the session. Today we will learn how to solve an equation. Let us start with taking an equality and an equation. So 9 minus 4 is equal to 4 plus 1 is an equality. As 9 minus 4 is equal to 5 and 4 plus 1 is also equal to 5. So that means these both are equal. Now x plus 5 is equal to 9 is an equation. Now to solve an equation or for an equality we should keep certain points in our mind. First is if we add the same number to both sides of an equality or equation. The same number of equality, equality and equation by the same non-zero number it still holds. Thus if we fail to do the same mathematical operation on both the sides of an equality or an equation then the equality or equation does not hold. Now let us see how to solve an equation. For this we will take an example. We need to solve the equation 2x plus 6 is equal to 12 where x is the variable and we need to find the value of x. So the given equation is 2x plus 6 is equal to 12. Now we will go stepwise to separate the variable x on the left hand side of the equation. Now left hand side is 2x plus 6. So first of all we will subtract 6 from both the sides to get 2x. So let us subtract 6 we get 2x plus 6 minus 6 is equal to 12 minus 6. Now plus 6 minus 6 will get cancelled so this gives us 2x is equal to 12 minus 6 is equal to 6. So we have 2x is equal to 6 that is left hand side by. So we will divide both the sides by 2 and we get 2x upon 2 is equal to 6 upon 2 which gives us x is equal to thus the value of x is 3 we substitute the value of x in the given equation. We have 2x plus 6 is equal to 12. Now we will take LHS let us substitute the value of x we have 2x plus 6. So this will be equal to 3 plus 6 that is we get LHS is equal to RHS thus our answer x equal to 3 is correct using another method that is the number instead of adding or subtracting it from both the sides of the equation. The equation that is 2x plus 6 is equal to 12 we have 2x plus 6. So first of all we will transpose is equal to 12 here we will have minus 6 as the sign of plus 6 will change. So this gives us 2x is equal to 6 now we will divide both the sides by 2 upon 2 is equal to 6 upon 2. And this gives us x is equal to 2 we can use any of these methods that is adding or subtracting on both the sides. Now let us solve one more equation which involves bracket we have 3 into n minus 5 is equal to minus 21. Here n is the variable the value of n. So here the given equation is 3 into n minus 5 is equal to minus 21. Bracket from LHS we will divide both the sides by 3. So we get 3 into n minus 5 upon 3 is equal to minus 21 upon 3 this gives us n minus 5 is equal to minus 7. Here let us use the method of transposing a number. So let us transpose minus 5 from LHS to RHS and thus the sign of minus 5 will change. So we get n is equal to minus 7 so this gives us n need to check our hands. Let us take the equation that is 3 into n minus 5 is equal to minus 21. Let us substitute the value of n in LHS. LHS is equal to 3 into n minus 5. So this will be equal to 3 into minus 2 minus 5 which is equal to 3 into minus 7 that is minus 21. And RHS is also equal to minus 21 thus LHS is equal to RHS so our answer n is equal to minus 2 is correct. So we have learnt how to solve an equation. With this we have finished this session. Hope you must have understood all the concepts.