P=15x2+600x+60

Solution for P=15x2+600x+60 equation:

=15P^2+600P+60

We move all terms to the left:

-(15P^2+600P+60)=0

We get rid of parentheses

-15P^2-600P-60=0

a = -15; b = -600; c = -60;
Δ = b2-4ac
Δ = -6002-4·(-15)·(-60)
Δ = 356400
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:

$\sqrt{\Delta}=\sqrt{356400}=\sqrt{32400*11}=\sqrt{32400}*\sqrt{11}=180\sqrt{11}$
$P_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-600)-180\sqrt{11}}{2*-15}=\frac{600-180\sqrt{11}}{-30}
$
$P_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-600)+180\sqrt{11}}{2*-15}=\frac{600+180\sqrt{11}}{-30}
$