[tex] - {p}^{2} - 12 = p \\ {p}^{2} - 12 - p = 0 \\ {p}^{2} - p - 12 = 0[/tex]
Now, use the mid term splitting technique
[tex] {p}^{2} - 4p + 3p - 12 \\ = p(p - 4) + 3(p - 4) \\ = (p + 3)(p - 4) \\ \\ \\ \\ [/tex]
From here
we'll do the same thing we do to find the zeroes,
p+3=0 or p -4 =0
p = -3 or p = 4
Therefore
p = -3 and 4
