P=d2+4d-4

Solution for P=d2+4d-4 equation:

=P2+4P-4

We move all terms to the left:

-(P2+4P-4)=0

We add all the numbers together, and all the variables

-(+P^2+4P-4)=0

We get rid of parentheses

-P^2-4P+4=0

We add all the numbers together, and all the variables

-1P^2-4P+4=0

a = -1; b = -4; c = +4;
Δ = b2-4ac
Δ = -42-4·(-1)·4
Δ = 32
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$P_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$P_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{32}=\sqrt{16*2}=\sqrt{16}*\sqrt{2}=4\sqrt{2}$
$P_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-4)-4\sqrt{2}}{2*-1}=\frac{4-4\sqrt{2}}{-2}
$
$P_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4)+4\sqrt{2}}{2*-1}=\frac{4+4\sqrt{2}}{-2}
$