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# I Need Help On Algebraic Fractions!

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1. Heya, im doing a past paper for the exam on Monday, it's a non calculator and I am stuck on a similar sort of question.

What I did was:

I multiplied out the numerator and then cross multiplied the denominator onto the other side of the equals sign:

Here is where i got stuck..
I had to options, either follow what Mathswatch had taught me and rearrange the whole equation to make 0 then factorise or use the quadratic formula..
Since this is a non calculator i attempted the rearranging and factorising:

I tried the ABC method ( a=2 .. b= -21 .. c= 37)
The rule is which would in this case
The factors of 74 are : 1 and 74, 2 and 37 and neither of these add or subtract to make B which is -21..

So I'm either lost, over complicating things or completely wrong!
2. (Original post by Winch2012)
Heya, im doing a past paper for the exam on Monday, it's a non calculator and I am stuck on a similar sort of question.

What I did was:

I multiplied out the numerator and then cross multiplied the denominator onto the other side of the equals sign:

Here is where i got stuck..
I had to options, either follow what Mathswatch had taught me and rearrange the whole equation to make 0 then factorise or use the quadratic formula..
Since this is a non calculator i attempted the rearranging and factorising:

I tried the ABC method ( a=2 .. b= -21 .. c= 37)
The rule is which would in this case
The factors of 74 are : 1 and 74, 2 and 37 and neither of these add or subtract to make B which is -21..

So I'm either lost, over complicating things or completely wrong!
I believe you're right - there's no simple solution, and you'd just have to give it in terms of the quadratic formula. http://www.wolframalpha.com/input/?i...%29%5E-1+%3D+2
My calculator came out with a solution of 8.26.... so yeah, there's no simple solution

Edit: Wolfram Alpha - the most amazing maths tool on the internet it's soo good
3. (Original post by Junaid96)
I believe you're right - there's no simple solution, and you'd just have to give it in terms of the quadratic formula. http://www.wolframalpha.com/input/?i...%29%5E-1+%3D+2
My calculator came out with a solution of 8.26.... so yeah, there's no simple solution

Edit: Wolfram Alpha - the most amazing maths tool on the internet it's soo good
The question was non-calculator.
4. Yeah however, the mark scheme says that X = 5 or X = -0.5

The brief explanation is:
M1 for common denominator on LHS or clearing fractions
M1 for multiplying out brackets
A1 for
M1 for (2x ± 1)(x ± 5) or substitution into quadratic formula
A1 for 5 and - 0.5
5. (Original post by ThatPerson)
The question was non-calculator.
True, but that doesn't stop you using the formula:
(21+Sqrt137)/4 or (21-Sqrt137)/4 being the solutions as I get them
6. (Original post by ThatPerson)
The question was non-calculator.
Yes, I know. I just used a calculator to confirm my suspicions.

(Original post by Icedstoat)
True, but that doesn't stop you using the formula:
(21+Sqrt137)/4 or (21-Sqrt137)/4 being the solutions as I get them
Yep, and as I said in my OP, "you'd just have to give it in terms of the quadratic formula"
(Original post by Winch2012)
Yeah however, the mark scheme says that X = 5 or X = -0.5

The brief explanation is:
M1 for common denominator on LHS or clearing fractions
M1 for multiplying out brackets
A1 for
M1 for (2x ± 1)(x ± 5) or substitution into quadratic formula
A1 for 5 and - 0.5
but.. 5 isn't a solution?
7. (Original post by Junaid96)
...
(Original post by Icedstoat)
...
(Original post by Winch2012)
Yeah however, the mark scheme says that X = 5 or X = -0.5

The brief explanation is:
M1 for common denominator on LHS or clearing fractions
M1 for multiplying out brackets
A1 for
M1 for (2x ± 1)(x ± 5) or substitution into quadratic formula
A1 for 5 and - 0.5
(Original post by ThatPerson)
...
There is a typo.

The question should be

The minus sign should be positive.
8. OP, if that's the mark scheme, then you've probably misread the question or something.
9. (Original post by Icedstoat)
OP, if that's the mark scheme, then you've probably misread the question or something.
See my previous post.
10. Yeah, I really need to learn to type faster before someone else says what I'm about to say
11. THANKS SO MUCH!
I literally spent hours on this question !!

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