16^2=x^2+9x

Solution for 16^2=x^2+9x equation:

16^2=x^2+9x

We move all terms to the left:

16^2-(x^2+9x)=0

We add all the numbers together, and all the variables

-(x^2+9x)+256=0

We get rid of parentheses

-x^2-9x+256=0

We add all the numbers together, and all the variables

-1x^2-9x+256=0

a = -1; b = -9; c = +256;
Δ = b2-4ac
Δ = -92-4·(-1)·256
Δ = 1105
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-9)-\sqrt{1105}}{2*-1}=\frac{9-\sqrt{1105}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-9)+\sqrt{1105}}{2*-1}=\frac{9+\sqrt{1105}}{-2}
$