Method for simultaneous equations of two or more variables, Mathematics

Assignment Help:

Method

In this method we eliminate either x or y, get the value of other variable and then substitute that value in either of the original equations to get the value of the other variable. Let us look at it.

We are given two equations 3x + 4y = 10 and 4x + y = 9. We write them as follows.

      3x + 4y = 10                                       ........(1)

      4x + y  = 9                                         ........(2)

In this example, let us eliminate y. Multiply equ. (2) by 4. We have

      4(4x + y = 9)

which is   16x + 4y = 36                             ........(3)

We observe that the coefficients of y in equations (1) and (3) are one and the same, and therefore, we subtract equ.(1) from equ.(3).

16x + 4y = 36   

- (3x + 4y = 10) 


13x + 0  = 26   


At this point one should remember that the signs of equation (1) should be changed before subtracting.

      13x      = 26

          x  = 26/13 = 2

We now substitute the value of x = 2 in either equ. (1) or (2). Let us substitute in equ. (2).

      4x + y      =   9

      4(2) + y    =   9

      8 + y        =   9

      y = 9 - 8   =   1

That is, the values of x and y for which both the equations are satisfied are x = 2 and y = 1.

We substitute these values in equ. (1) and check.

      3x + 4y       =   10

      3(2) + 4(1)  =   10

      6 + 4          =   10

      10              =   10

That is, LHS = RHS.


Related Discussions:- Method for simultaneous equations of two or more variables

Formula to computing how much lumber to buy, Audrey is creating a increased...

Audrey is creating a increased flowerbed which is 4.5 ft by 4.5 ft. She requires computing how much lumber to buy. If she requires knowing the distance around the flowerbed, which

What is identities and contradictions, What is Identities and Contradiction...

What is Identities and Contradictions ? Look at this equation: x + 1 = 1 + x It happens to be true always, no matter what the value of x. (Try it out! What if x is 43?)

Method of disks or the method of rings, Method of disks or the method of ri...

Method of disks or the method of rings One of the simple methods for getting the cross-sectional area is to cut the object perpendicular to the axis of rotation.  Carrying out

How much interest will she have made after 4 years, Celine deposited $505 i...

Celine deposited $505 into her savings account. If the interest rate of the account is 5% per year, how much interest will she have made after 4 years? Use the formula F = 9/5

Geometry , solve for x and y 2x+3y=12 and 30x+11y=112

solve for x and y 2x+3y=12 and 30x+11y=112

Play and learn maths, PLAY AND LEARN :  Children can learn many basic math...

PLAY AND LEARN :  Children can learn many basic mathematical concepts through games. They enjoy Mathematical concepts can be playing within familiar contexts. Their games also gen

Equation, how do you slove 4u-5=2u-13

how do you slove 4u-5=2u-13

Help with individual questions, Hi, I''m looking for assistance/solutions t...

Hi, I''m looking for assistance/solutions to individual questions. I''ve already answered them but seek confirmation my answers are correct. I don''t want answers to a complete e

Determine the volume of the pool, An inground pool is pooring with water. T...

An inground pool is pooring with water. The shallow end is 3 ft deep and gradually slopes to the deepest end, which is 10 ft deep. The width of the pool is 30 ft and the length is

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd