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Solve equation

I've been told to solve this equation and put it into surd form.

x^2-6x+2=0

I have never done this type of question before. What is the best way to approach and solve this question

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Reply 1
Do you know the quadratic formula?
Reply 2
Nope
Original post by zed963
Nope


Surely you do.

This one?

x=b±b24ac2a x = \dfrac{-b \pm \sqrt{b^2-4ac}}{2a}
Reply 4
Oh I've seen that on an exam paper formula sheet.
Reply 5
Original post by zed963
I've been told to solve this equation and put it into surd form.

x^2-6x+2=0

I have never done this type of question before. What is the best way to approach and solve this question


Asked by whom
For what purpose

There are 2 methods (essentially the same)
Use the formula as given above
Complete the square

If you do not know what either of these are then you cannot do this question


If your teacher has asked you to do this I suggest they teach you material first
Reply 6
Original post by TenOfThem
Asked by whom
For what purpose

There are 2 methods (essentially the same)
Use the formula as given above
Complete the square

If you do not know what either of these are then you cannot do this question


If your teacher has asked you to do this I suggest they teach you material first


My teacher hasn't taught me this its just in the book that i'm working from.

And why does everything have to depend on a teacher
Reply 7
Original post by zed963
My teacher hasn't taught me this its just in the book that i'm working from.

And why does everything have to depend on a teacher


Indeed.

If you're working through a book then it's almost definitely the case that the question you're being asked can be solved using material introduced in the preceding chapters. If the quadratic formula hasn't been introduced in the book before this question is asked, then it's likely that, at the very least, the method of completing the square has been introduced. So on that assumption, you could complete the square to get the answer.

If you're still unsure, flick through the book to find out how to solve quadratic equations.
Original post by zed963
My teacher hasn't taught me this its just in the book that i'm working from.

And why does everything have to depend on a teacher


If you don't want to depend on a teacher then surely you need to actually read the bit in the book that teaches this bit. If it's asking questions without previously explaining how to tackle these questions I suggest you get a new textbook.
Reply 9
Original post by zed963


And why does everything have to depend on a teacher



What alternative do you suggest

Do you think it is better asking on here rather than asking a teacher
Original post by zed963
My teacher hasn't taught me this its just in the book that i'm working from.

And why does everything have to depend on a teacher


In your first post you said "I've been told to solve this equation and put it into surd form"

So who TOLD you?
Original post by steve2005
In your first post you said "I've been told to solve this equation and put it into surd form"

So who TOLD you?


I think by told he means the question in the book says 'solve this equation and write your answer in surd form'.
Original post by zed963
I've been told to solve this equation and put it into surd form.

x^2-6x+2=0

I have never done this type of question before. What is the best way to approach and solve this question


I suggest you buy a textbook or take out a library book.
Original post by hassi94
I think by told he means the question in the book says 'solve this equation and write your answer in surd form'.


He is using various phrases to get us to teach him. He seems keen but unfortunately not keen enough to use a textbook or google.
Original post by zed963
My teacher hasn't taught me this its just in the book that i'm working from.

And why does everything have to depend on a teacher


For the quadratic formula you have A, B and C, and they are in the form:

ax2+bx+c ax^2+bx+c

Maybe that will help. For if there is no number, just X2 X^2 for example, take the number as 1.
(edited 11 years ago)
Original post by steve2005
He is using various phrases to get us to teach him. He seems keen but unfortunately not keen enough to use a textbook or google.


I know, I agree that he needs to be a bit more independent or use his teacher.


After all OP, this forum is for helping people when they struggle; not for outright teaching things. If you had read up about the quadratic equation but got stuck on this question then that's fine. But it's like you're not trying.
x²-6x+2=0

x²-6x=-2

x²-6x = (x-3)²-9 <--- since (x-3)² = x²-6x+9, you have to take 9.
------------------------------ Notice: (x-3)²... half of the 6 from x²-6x.
(x-3)² -9=-2 <---- Equate this back to x²-6x=-2

(x-3)²=7

(x-3)=±√7

x=3±√7

So; x=3+√7 or x=3-√7
(edited 11 years ago)
Original post by Transcendence
x²-6x+2=0

x²-6x = (x-3)²-9

(x-3)² -9=-2

(x-3)²=7

(x-3)=±7

x=3±7

x=10 or x=-4


Please don't give full solutions; and definitely don't give incorrect ones.
Reply 19


You are trying to learn concepts from scratch on TSR, it will be better if you watch video tutorials, to understand this stuff.

If you get a difficult question that you can't solve, then you should come here for help.

By the way, which chapter is this question from?

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