GCSE Maths Revision: Simultaneous Equations

A simultaneous equation includes two equations and RHS(right hand side) terms and requires you to find the unknowns. For example:

4x + 6y = 12

2x + 5y = 13

are simultaneous equations. The example shows how to solve them.

Solve the simultaneous equations

4x + 6y = 12

and

2x + 5y = 13

To solve simultaneous equations we need to multiply each x or y term by a number that will make one unknown equal in both equations. We then add(or subtract) one equation to the other one. In this case, to make the x's equal, we can multiply the top equation by 1 and the bottom one by 2. This gives:

4x + 6y = 12 (1)

and

4x + 10y = 26. (2)

If we subtract number 1 from number 2 we get :

0x + 4y = 14

y = 14/4 = 3.5.

Now, plugging this value back into any of the 2 equations (I'll go for number 2) gives:

4x + 10 X 3.5 = 26

4x + 35 = 26

4x = - 9

x = - 2.25. We've solved it! (To check, plug the values back into both equations)

In the case of simultaneous equations including fractions, get rid of the fractions and rearrage the equation so it looks like a normal one. Then solve it...........................................

For much more on Simultaneous Equations,

as well as Algebra, Probability, The Circle and much, much more, get Adam's unique, All-NEW Math, Maths Buster revision study guide e-Book! 116 pages packed full of detail, content, handy hints, questions and answers and more, and written in Adam's popular light-hearted and very easy to understand style, everything you need to help you get a top grade in your math or maths exam!

Plus, check out the NEW section on Graphs, as well as the top revision method Adam used to pass his GCSE maths exam with top grade A at just 9 years old!

It costs just £12.99 ($22 US), and you can have instant, immediate delivery and access as soon as you complete your order!

Grab the NEW Maths, Math Buster e-Book by Adam Spencer today!

CLICK HERE TO LEARN MORE AND ORDER NOW!

Copyright © 2001 P&AS. WebVisage. All Rights Reserved.
The contents of this site are subject to copyright.