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i have got some work which i dont understand how to do
i have to find x from the formula x^2+4x+4=0 i have no idea were to start i tried x^2+4x=4 then x(x+4)=4 so x=4 and x=1 but the back of the book says x=-2 is the book wrong?
i have to find x from the formula x^2+4x+4=0 i have no idea were to start i tried x^2+4x=4 then x(x+4)=4 so x=4 and x=1 but the back of the book says x=-2 is the book wrong?
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#2
(Original post by user6)
i have got some work which i dont understand how to do
i have to find x from the formula x^2+4x+4=0 i have no idea were to start i tried x^2+4x=4 then x(x+4)=4 so x=4 and x=1 but the back of the book says x=-2 is the book wrong?
i have got some work which i dont understand how to do
i have to find x from the formula x^2+4x+4=0 i have no idea were to start i tried x^2+4x=4 then x(x+4)=4 so x=4 and x=1 but the back of the book says x=-2 is the book wrong?
do you remember this from your GCSE?
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#3
You aren't facorising it correctly. What you should be trying to do is trying to split x^2 + 4x + 4 into 2 brackets. E.g (x * ?)(x * ?)
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(Original post by TeeEm)
factorize the quadratic or use the quadratic formula.
do you remember this from your GCSE?
factorize the quadratic or use the quadratic formula.
do you remember this from your GCSE?
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(Original post by AwesomeSauce#1)
Aren't facorising it correctly. What you should be trying to do is be trying to split x^2 + 4x + 4 into 2 brackets. E.g (x * ?)(x * ?)
Aren't facorising it correctly. What you should be trying to do is be trying to split x^2 + 4x + 4 into 2 brackets. E.g (x * ?)(x * ?)
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#6
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#7
(Original post by user6)
i did factorize it but the answer is wrong? i dont think we done quadratic formula yet
i did factorize it but the answer is wrong? i dont think we done quadratic formula yet
factorize into 2 brackets with the right hand side = 0
(x+...)(x+...)=0
does this ring any bells?
PS what course are you doing?
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#8
(Original post by user6)
i have got some work which i dont understand how to do
i have to find x from the formula x^2+4x+4=0 i have no idea were to start i tried x^2+4x=4 then x(x+4)=4 so x=4 and x=1 but the back of the book says x=-2 is the book wrong?
i have got some work which i dont understand how to do
i have to find x from the formula x^2+4x+4=0 i have no idea were to start i tried x^2+4x=4 then x(x+4)=4 so x=4 and x=1 but the back of the book says x=-2 is the book wrong?
Have you learned how to solve quadratic equations?
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(Original post by TeeEm)
book is correct
factorize into 2 brackets with the right hand side = 0
(x+...)(x+...)=0
does this ring any bells?
PS what course are you doing?
book is correct
factorize into 2 brackets with the right hand side = 0
(x+...)(x+...)=0
does this ring any bells?
PS what course are you doing?
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(Original post by davros)
Your method doesn't work - try putting x = 1 or x = 4 into your original equation and you'll see why!
Have you learned how to solve quadratic equations?
Your method doesn't work - try putting x = 1 or x = 4 into your original equation and you'll see why!
Have you learned how to solve quadratic equations?
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#11
(Original post by user6)
not sure what u are doing how do I get 0 from my formula? and how do I get the 2 brackets?
not sure what u are doing how do I get 0 from my formula? and how do I get the 2 brackets?
You shouldn't be trying to tackle something like this if you haven't been taught the method to begin with
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#13
(Original post by user6)
not sure what u are doing how do I get 0 from my formula? and how do I get the 2 brackets?
not sure what u are doing how do I get 0 from my formula? and how do I get the 2 brackets?
if (x-2)(x+5)=0
then either
x-2=0
x=2
or
x+5=0
x=-5
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#14
(Original post by user6)
whats wrong with x=1? 1^2+4+4=9 whats wrong?
whats wrong with x=1? 1^2+4+4=9 whats wrong?
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(Original post by davros)
Have you been through this in class or with a teacher?
You shouldn't be trying to tackle something like this if you haven't been taught the method to begin with
Have you been through this in class or with a teacher?
You shouldn't be trying to tackle something like this if you haven't been taught the method to begin with
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#16
(Original post by user6)
how do i do this because (x+4)(x+4)=x^2+16 how does that help?
how do i do this because (x+4)(x+4)=x^2+16 how does that help?
(x + 4)(x + 4) = x^2 + 8x + 16.
Have you covered multiplying brackets in class?
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#18
(Original post by user6)
I have to teach myself (cannot afford a teacher lol) because i failed gcse maths and sixth form is making me resit
I have to teach myself (cannot afford a teacher lol) because i failed gcse maths and sixth form is making me resit
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(Original post by davros)
That's not true either!
(x + 4)(x + 4) = x^2 + 8x + 16.
Have you covered multiplying brackets in class?
That's not true either!
(x + 4)(x + 4) = x^2 + 8x + 16.
Have you covered multiplying brackets in class?
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