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Help with algebraic fraction

Louish99

Hi all, i need help with the following question that has previously appeared in calculator exams.

Thanks for any help

Reply 1

Zacken

Original post by Louish99

Hi all, i need help with the following question that has previously appeared in calculator exams.

Thanks for any help

Try factorising both the numerator and denominator? See if there are any common factors, cancel.

Reply 2

poorform

As above.

You should spot that the top is a difference of two squares and that factorizes immediately. Given the fact this is a simplify question you should be expecting one of the factors on the top to be the same as one on the bottom so you can deduce how the bottom one factors as well pretty much straight away. Or you can write it all down if you are more comfortable with that.

Reply 3

vanessa_rb

Hiya, I played around with it and got this - I tried to write it so you could see where I got the answers from but obviously don't write it out like that in an exam. If you have trouble factorising the denominator and it's calc you can always do the good old quadratic formula!

Reply 4

Zacken

Original post by vanessa_rb

It would be good if you could place your image in a spoiler so the OP can check AFTER he has completed the question. The aim here is to provide help but not the answer, just hints so that they can work it out for them. :smile:

Reply 5

Man.bear.pig

Original post by Zacken

Try factorising both the numerator and denominator? See if there are any common factors, cancel.

was gonna say :colonhash:

Original post by Louish99

Hi all, i need help with the following question that has previously appeared in calculator exams.

Thanks for any help

Yep.
The numerator is quite simple because both are perfect square. just find the perfect square for 4x and 25, and think about your + and - signs.
You should get

Spoiler

Do you need help with the denominator? :smile:

Reply 6

Zacken

Original post by vanessa_rb

Haha I know, but if they have an exam soon and need to know for future ref I'd like to think if they could get the technique correct now then they can apply it in the exam or find more similar questions! :smile:

And they would be able to apply the technique better if they had learn the technique by struggling through a question rather than just copying down the solution someone else wrote for them. That's why, at the very least, I asked you to edit your post and put the image in a spoiler box so that they can check your method AFTER doing the question themselves.