256+x^2=900

Solution for 256+x^2=900 equation:

256+x^2=900

We move all terms to the left:

256+x^2-(900)=0

We add all the numbers together, and all the variables

x^2-644=0

a = 1; b = 0; c = -644;
Δ = b2-4ac
Δ = 02-4·1·(-644)
Δ = 2576
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{2576}=\sqrt{16*161}=\sqrt{16}*\sqrt{161}=4\sqrt{161}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-4\sqrt{161}}{2*1}=\frac{0-4\sqrt{161}}{2}
=-\frac{4\sqrt{161}}{2}
=-2\sqrt{161}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+4\sqrt{161}}{2*1}=\frac{0+4\sqrt{161}}{2}
=\frac{4\sqrt{161}}{2}
=2\sqrt{161}
$