Elimination Method to Solve Simultaneous Equations

Today we are going to learn about Simultaneous solving equations. In case we have two equations with two variables to be solved , we call them Simultaneous Equations. We have different  Method to  Solve Simultaneous Equations, among which most common are LPP and Elimination Method to Solve Simultaneous Equations. (Also improve your skills in graphing linear equations)

Here we are going to learn about Elimination Method to Solve Simultaneous Equations.
In this method, let us say we have two variables x and y in the given two equations. We first find the value of x in form of y and put that value of x in the second equation.
By this method, we eliminate one variable from the equation and the equation is left with only one variable. So we simply find the solution of the equation in one variable .
In this way the value of one variable is solved. Putting the value of one variable in the first equation and we get the value of another variable also. Get more detail here.
Let us learn it through an example:
Solve the given pair of equations: x + y = 10 ------ (1)
                                               and 2x + y = 14 ----- (2)
Sol : from First equation: x + y = 10
     We can  get      y = 10 - x  ----- (3)
   From the above  we put the value of y from  (3)  in (2)
  This is called elimination of y from (2) equation.
we get , 2x  + ( 10 - x ) = 14
  or, 2x +10 - x = 14
  or,  2x - x = 14 - 10
 or, x = 4 is the value of x
Now putting this value in (3)  we get
  or, y = 10 - 4
 or  y = 6 Ans.

In this way two values of x and y can be solved by eliminating one variable from the equation.

In upcoming posts we will discuss about Linear Equations Word Problems and How to find Median. Visit our website for information on CBSE board physics syllabus