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# Can any help with this As level maths core 1 quadratic function question?

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1. I'm a little bit stuck on this question and was wondering if anyone can help.
The question is:
'The equation x^2 + 2px + (3p+4) =0 where p is a positive constant, has equal roots. Find the value of p (4 marks)'
So far I have this:
a=1 b=2p c=(3p+4). b^2 -4ac. (The discriminant)
(2p)^2 - (4 x 1 x (3p+4)
4p^2 = (4 x 1 x (3p+4)
4p^2 =12p +16
p^2= 3p + 4

But now I am not sure what to do, any help will be greatly appreciated
2. All you have to do now is solve the quadratic by factorisation:

3. p^2 - 3p - 4 = 0
(p - 4)(p + 1) = 0

Since it's positive p = 4

Ninja'd ;o;
4. (Original post by NeverLucky)
All you have to do now is solve the quadratic by factorisation:

Thank you... Turns out I was factorising it wrong when I tried
5. (Original post by Imperion)
p^2 - 3p - 4 = 0
(p - 4)(p + 1) = 0

Since it's positive p = 4

Ninja'd ;o;
Thank you

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