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SAI International School

Mathematics
Chapter-3- Pair of Linear Equations in Two Variables-2
Lesson Notes -2

Sub topics: Algebraic Methods of solving a Pair of Linear Equations

The solution of a pair of linear equation in two variables ‘x’ and ‘y’ is a pair of values
(one for ‘x’ and other for ‘y’) which satisfies both the equations.

There are two types of methods to solve a pair of linear equations:

(i) Graphical method (Taught in previous Module)

(ii) Algebraic method

Algebraic Method of Solving a Pair of Linear Equations

Different methods to solve a pair of linear Equations are

(i) Substitution Method
(ii) Elimination Method
(iii) Cross- Multiplication Method
(iv) Special Method

Substitution Method:

Step 1- Find the value of one variable in terms of the other from any one equation.

Step 2 – Substitute this value in the other equation to reduce it to a linear equation in
one variable and solve the equation in one variable.

Step 3- Substitute the value of the variable obtained, in either of the original equation to
obtain the value of the other variable.

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