8x2+5=285

Solution for 8x2+5=285 equation:

8x^2+5=285

We move all terms to the left:

8x^2+5-(285)=0

We add all the numbers together, and all the variables

8x^2-280=0

a = 8; b = 0; c = -280;
Δ = b2-4ac
Δ = 02-4·8·(-280)
Δ = 8960
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:

$\sqrt{\Delta}=\sqrt{8960}=\sqrt{256*35}=\sqrt{256}*\sqrt{35}=16\sqrt{35}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-16\sqrt{35}}{2*8}=\frac{0-16\sqrt{35}}{16}
=-\frac{16\sqrt{35}}{16}
=-\sqrt{35}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+16\sqrt{35}}{2*8}=\frac{0+16\sqrt{35}}{16}
=\frac{16\sqrt{35}}{16}
=\sqrt{35}
$