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# Re-arranging surd in form a+b(root)5 watch

1. The original question said: express (2)/((3(root)5+7) in the form a+b(root)5, I've gotten up the last bit of it which is:

= (6(root)5 - 14)/(45-49)
= (6(root)5 - 14)/-4 then simplified as 2 goes into 6, -14 and -4
= (3(root)5 - 7)/-2
= (3(root)5)/-2 + -7/-2
= (3(root)5)/-2 + 7/2

The markscheme says the -2 shouldn't be under my 3(root)5 surd and should be a positive 2, so where have I gone wrong?
2. Is the numerator in the question wrong?

3 x 3 does not equal 6.

3 x -7 does not equal -14.
3. Finally
4. And in today's lesson, we learnt how to multiply by 1 . . .
5. (Original post by Mr M)
Is the numerator in the question wrong?

3 x 3 does not equal 6.

3 x -7 does not equal -14.
yes sorry, the numerator was supposed to be 2
6. (Original post by Magenta96)
yes sorry, the numerator was supposed to be 2
So do you understand the answer now?
7. (Original post by Mr M)
So do you understand the answer now?
Yes, I've got the right answer now, do you think I'd still lose marks for not giving the same denominators for both terms? because it is in the form they asked

Thank you
8. (Original post by Magenta96)
Yes, I've got the right answer now, do you think I'd still lose marks for not giving the same denominators for both terms? because it is in the form they asked

Thank you
No but it is normal to write negative fractions as rather than
9. (Original post by Mr M)
No but it is normal to write negative fractions as rather than
ok thanks

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