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# Easy method for adding or taking away algebraic equations? Tweet

Maths and statistics discussion, revision, exam and homework help.

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1. Easy method for adding or taking away algebraic equations?
Hi

Could someone please remind me how to add or take away algebraic equations? Im revising for C3 (Differentiation) and I seem to struggle with the last step of answering questions.

For example, how to take away:

( (2x−1)^2 X 6x ) − (3x^2 X 4(2x−1) )

I've left it in the above form because thats how its written in the solution I have but I cant work out why the answer is:

6x(2x−1)[(2x−1)−2x]

Sorry this seems to be a basic thing but I cannot remember how to do it. Im on a gap year and decided to do this A2 maths course so I dont have a teacher at this moment.

2. Re: Easy method for adding or taking away algebraic equations?
(Original post by amani-puresapphire)
Hi

Could someone please remind me how to add or take away algebraic equations? Im revising for C3 (Differentiation) and I seem to struggle with the last step of answering questions.

For example, how to take away:

( (2x−1)^2 X 6x ) − (3x^2 X 4(2x−1) )

I've left it in the above form because thats how its written in the solution I have but I cant work out why the answer is:

6x(2x−1)[(2x−1)−2x]

Sorry this seems to be a basic thing but I cannot remember how to do it. Im on a gap year and decided to do this A2 maths course so I dont have a teacher at this moment.

Now pull out, , as a common factor.
3. Re: Easy method for adding or taking away algebraic equations?
(Original post by amani-puresapphire)
Hi

Could someone please remind me how to add or take away algebraic equations? Im revising for C3 (Differentiation) and I seem to struggle with the last step of answering questions.

For example, how to take away:

( (2x−1)^2 X 6x ) − (3x^2 X 4(2x−1) )

I've left it in the above form because thats how its written in the solution I have but I cant work out why the answer is:

6x(2x−1)[(2x−1)−2x]

Sorry this seems to be a basic thing but I cannot remember how to do it. Im on a gap year and decided to do this A2 maths course so I dont have a teacher at this moment.

Find a common factor in each.

E.g. 6x(3x+2) - 7(3x+2)² = (3x+2)(6x) - (3x+2)(3x+2)(7) = (3x+2)(6x - 7(3x+2)) = (3x+2)(-15x - 14)
4. Re: Easy method for adding or taking away algebraic equations?
(Original post by raheem94)

Now pull out, , as a common factor.
Thank you both soooo much! I cannot believe I didnt think of asking on here sooner.