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factorising quadratic equations

Just needed help on these questions and if someone can check if i did them correctly thank you so much image is below X

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Yeah you did them correctly, well done!
Reply 3
The first one both solution are right but the second one the factors should be (x-4) (x+3) so x=4 and x=-3
and you can make sure your solutions are right by multiplying the brackets you found and if you get the same quadratic equation as the start so your xs are right if not so u have factorised it wrong
(edited 7 years ago)
Reply 4
Original post by iMacJack
Yeah you did them correctly, well done!


Thank you so much, that's all I needed to check :smile: x
I had a feeling I made a mistake in the second one because I'm not so confident on quadratics.

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No 2 is wrong because you need -12 :smile:
Original post by iMacJack
Yeah you did them correctly, well done!


she did no 2 wrong:s-smilie:
Oh yes I think you did sorry! Second one should be (x-4)(x+3) - I skim read it as +3!

@Ayaz789 @z_o_e
Original post by z_o_e
Thank you so much, that's all I needed to check :smile: x
I had a feeling I made a mistake in the second one because I'm not so confident on quadratics.

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It should be (x-4)(x+3) Just a slight mistake, dw about it!:smile:
Reply 9
Original post by Ayaz789
No 2 is wrong because you need -12 :smile:


Yess i knew it.

How do i change it?

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Original post by iMacJack
Oh yes I think you did sorry! Second one should be (x-4)(x+3) - I skim read it as +3!

@Ayaz789 @z_o_e


Haha yeah its fine , i make many silly mistakes myself:u:
Original post by z_o_e
Yess i knew it.

How do i change it?

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It should be (x-4)(x+3) Just a slight mistake, dw about it!
Original post by z_o_e
Yess i knew it.

How do i change it?

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You have broken it up into
x^2 - 4x - 3x - 12 = 0
When it should be
x^2 - 4x + 3x - 12 = 0

:smile:
Reply 13
Original post by Ayaz789
It should be (x-4)(x+3) Just a slight mistake, dw about it!

Ohhh I made a little mistake with the sign haha


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Reply 14
Thank you guys for the replies! :smile:

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Original post by z_o_e
Ohhh I made a little mistake with the sign haha


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Yeah perfect , keep going!:biggrin:
Reply 16
Original post by Ayaz789
Yeah perfect , keep going!:biggrin:




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I don't understand this part. When you have odd numbers and you can't find what goes into it and when you add and take them away you get 2.
Original post by z_o_e
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I don't understand this part. When you have odd numbers and you can't find what goes into it and when you add and take them away you get 2.


Okay so you always equal the right hand side to 0 , so take away 5 from both sides first!
Original post by z_o_e
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I don't understand this part. When you have odd numbers and you can't find what goes into it and when you add and take them away you get 2.


So you get t^2+2t-24=0 . then carry on from that :smile:
Reply 19
Original post by Ayaz789
So you get t^2+2t-24=0 . then carry on from that :smile:




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