# Really Hard Maths

Watch
Announcements

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?

0

reply

Report

#2

(Original post by

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?

**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?

do you remember this from your GCSE?

0

reply

Report

#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 * ?)

0

reply

(Original post by

factorize the quadratic or use the quadratic formula.

do you remember this from your GCSE?

**TeeEm**)factorize the quadratic or use the quadratic formula.

do you remember this from your GCSE?

0

reply

(Original post by

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 * ?)

**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 * ?)

0

reply

Report

#6

0

reply

Report

#7

(Original post by

i did factorize it but the answer is wrong? i dont think we done quadratic formula yet

**user6**)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?

0

reply

Report

#8

**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?

Have you learned how to solve quadratic equations?

0

reply

(Original post by

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?

**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?

0

reply

(Original post by

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?

**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?

0

reply

Report

#11

(Original post by

not sure what u are doing how do I get 0 from my formula? and how do I get the 2 brackets?

**user6**)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

0

reply

0

reply

Report

#13

**user6**)

not sure what u are doing how do I get 0 from my formula? and how do I get the 2 brackets?

**for example**

if (x-2)(x+5)=0

then

**either**

x-2=0

x=2

**or**

x+5=0

x=-5

0

reply

Report

#14

(Original post by

whats wrong with x=1? 1^2+4+4=9 whats wrong?

**user6**)whats wrong with x=1? 1^2+4+4=9 whats wrong?

0

reply

(Original post by

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

**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

0

reply

Report

#16

(Original post by

how do i do this because (x+4)(x+4)=x^2+16 how does that help?

**user6**)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?

0

reply

0

reply

Report

#18

(Original post by

I have to teach myself (cannot afford a teacher lol) because i failed gcse maths and sixth form is making me resit

**user6**)I have to teach myself (cannot afford a teacher lol) because i failed gcse maths and sixth form is making me resit

0

reply

(Original post by

That's not true either!

(x + 4)(x + 4) = x^2 + 8x + 16.

Have you covered multiplying brackets in class?

**davros**)That's not true either!

(x + 4)(x + 4) = x^2 + 8x + 16.

Have you covered multiplying brackets in class?

0

reply

X

### Quick Reply

Back

to top

to top