Common mistakes in transposing for X

July 24, 2020
SAC Tutoring

Transposition for X is a key skill required when solving most algebra equations. Such as the examples below.


https://www.onlinemathlearning.com/algebra-lesson-trans.html


There are several ways you could be solving these types of equations wrong.


1. Forgetting to change the signs when transposing.


For example:

2x+7=7 solve for x


    Instead of turning the +7 into a -7                             You bring the +7 over to the other side. [incorrect!]


Remember the opposites:


2. Adding Unlike Terms


Eg. If you have 3 bananas and 4 apples

Let a=apples and b=banana

3b + 4a = 3b + 4a


Not 3b + 4a = 7ab  


You can't add apples and bananas together!


Like terms have the same letters at the end.

For example:

4a + 4a = 8a


Both of the terms have an a at the end so we can add the numbers together.


3. Not writing every step down


A very common mistake students make is not writing steps down, using mental math. This majority of the time creates many mistakes, even small ones like adding or subtracting wrong. Sometimes teachers don’t give you a grade for working out however always best to.  


The most certain way to prevent any mistakes is to practice, practice, practice. This eliminates your any mistakes thus you will not lose marks. There are some links down below that you can use to practice. Questions and answers are provided.  

  1. http://www.staff.vu.edu.au/mcaonline/units/algebra/algtrans.html
  2. https://www.math10.com/en/algebra/simple-equations/simple-equations.html
  3. https://portal.uea.ac.uk/documents/6207125/8194887/steps+into+algebra+rearranging+equations+worksheet.pdf
  4. http://www.mathcentre.ac.uk/resources/workbooks/mathcentre/web-formulae2-tom.pdf

For more tips and tricks, check out our other blog posts. For more personalized advice, sign up for a free trial class with us. Check out our website for more info!

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