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1. Algebraic Fractions
I have this question

But I'm getting the wrong answer.

2. Re: Algebraic Fractions
I have to work out the value of X but I don't know how to.
3. Re: Algebraic Fractions
You are correct so far. Next, you can silmplify the 3x and the 4x on the numerator.

After that, move the to the right-hand side i.e. multiply both sides by . Then simplify and solve.
4. Re: Algebraic Fractions
(Original post by notnek)
You are correct so far. Next, you can silmplify the 3x and the 4x on the numerator.

After that, move the to the right-hand side i.e. multiply both sides by . Then simplify and solve.
So I've simplified the numerator,

and what exactly do you mean when you times the whole fraction by x^2
5. Re: Algebraic Fractions
And what's the best method to solve these type of questions.

The book shows a different method to what I am doing,

However I am now starting to get confused when it comes to simplifying algebraic fraction when it involves cancelling things out etc.
6. Re: Algebraic Fractions
Multiply the whole equation by (x^2 + x) and then rearrange to get it in the form of ax^2 + bx + c = 0 then factorise to work out the values of x
7. Re: Algebraic Fractions
(Original post by zed963)
And what's the best method to solve these type of questions.

The book shows a different method to what I am doing,

However I am now starting to get confused when it comes to simplifying algebraic fraction when it involves cancelling things out etc.
Usually you just have to get rid of all denominators and then solve for x.
8. Re: Algebraic Fractions
(Original post by zed963)
So I've simplified the numerator,

and what exactly do you mean when you times the whole fraction by x^2
You seem to have mislaid the whole =1 part of the question
9. Re: Algebraic Fractions
(Original post by TenOfThem)
You seem to have mislaid the whole =1 part of the question
Oops, so what is the best way of doing this question?

And please can you show me an example solution to this type of question.

Thanks.
10. Re: Algebraic Fractions
(Original post by zed963)
Oops, so what is the best way of doing this question?

And please can you show me an example solution to this type of question.

Thanks.
e.g.

Here I've moved the to the right-hand-side. Does this make sense to you?

Try to do a similar thing for your question. Then simplify and solve the resulting quadratic equation.
11. Re: Algebraic Fractions
Your method is fine

you are at the point of

So that means

12. Re: Algebraic Fractions
(Original post by TenOfThem)
Your method is fine

you are at the point of

So that means

so

x^2+2x-3

when rearranged.
13. Re: Algebraic Fractions
(Original post by zed963)
so

x^2+2x-3

when rearranged.
What happened to the equals sign?

If you start with an equation then you should still have an equation after you rearrange.
14. Re: Algebraic Fractions
(Original post by notnek)
What happened to the equals sign?
Again
15. Re: Algebraic Fractions
(Original post by notnek)
What happened to the equals sign?

If you start with an equation then you should still have an equation after you rearrange.
I forgot the =0 bit

Typo

But from then on when I factorise the equation I get

Thank you for explaining how to solve this equation to me.

Much appreciated
16. Re: Algebraic Fractions
(Original post by zed963)

Much appreciated
Sometimes you get a fraction on the RHS too, then it makes sense to simply multiply through by the common denominator from the start

eg

would become

which gives

giving

17. Re: Algebraic Fractions
I have this question and so far I have an idea of what I am doing but from there on I don't know what to do

Here's my working out.

How should I carry on with this question?
18. Re: Algebraic Fractions
(Original post by zed963)
I have this question and so far I have an idea of what I am doing but from there on I don't know what to do

Here's my working out.

How should I carry on with this question?

Can you work it out from there?
19. Re: Algebraic Fractions
(Original post by Groat)

Can you work it out from there?
Yes I originally thought of that

so if I did the root of 2.5 it gives +1.58 and -1.58
20. Re: Algebraic Fractions
The answer in the book is -1.5 and 2