C1 question (completing the square or quadratic formula)

Hello my good friends, i aced this question (or so i thought) and was proper chuffed, until i looked at the mark scheme.

http://www.examsolutions.net/a-level-maths-papers/Edexcel/Core-Maths/Core-Maths-C1/2009-June/paper.php

Q11

I got to the value it wnated through using completing the suare and not formula, but the mark scheme makes no mention of using completing the square and only using the formula. So would i still get the marks if i did it using compelting the square?

Hello my good friends, i aced this question (or so i thought) and was proper chuffed, until i looked at the mark scheme.

http://www.examsolutions.net/a-level-maths-papers/Edexcel/Core-Maths/Core-Maths-C1/2009-June/paper.php

Q11

I got to the value it wnated through using completing the suare and not formula, but the mark scheme makes no mention of using completing the square and only using the formula. So would i still get the marks if i did it using compelting the square?

Surely the mark scheme says "by formula or completing the square" so what are you worried about?

I don't see anything about completing the square on the mark scheme, i'm not so good at words and letters stuff so maybe you lads could take a look?

Hello my good friends, i aced this question (or so i thought) and was proper chuffed, until i looked at the mark scheme.

http://www.examsolutions.net/a-level-maths-papers/Edexcel/Core-Maths/Core-Maths-C1/2009-June/paper.php

Q11

I got to the value it wnated through using completing the suare and not formula, but the mark scheme makes no mention of using completing the square and only using the formula. So would i still get the marks if i did it using compelting the square?