63x-x^2=810

Solution for 63x-x^2=810 equation:

63x-x^2=810

We move all terms to the left:

63x-x^2-(810)=0

We add all the numbers together, and all the variables

-1x^2+63x-810=0

a = -1; b = 63; c = -810;
Δ = b2-4ac
Δ = 632-4·(-1)·(-810)
Δ = 729
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{729}=27$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(63)-27}{2*-1}=\frac{-90}{-2}
=+45
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(63)+27}{2*-1}=\frac{-36}{-2}
=+18
$