5x^2+8x+4=520

Solution for 5x^2+8x+4=520 equation:

5x^2+8x+4=520

We move all terms to the left:

5x^2+8x+4-(520)=0

We add all the numbers together, and all the variables

5x^2+8x-516=0

a = 5; b = 8; c = -516;
Δ = b2-4ac
Δ = 82-4·5·(-516)
Δ = 10384
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:

$\sqrt{\Delta}=\sqrt{10384}=\sqrt{16*649}=\sqrt{16}*\sqrt{649}=4\sqrt{649}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(8)-4\sqrt{649}}{2*5}=\frac{-8-4\sqrt{649}}{10}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(8)+4\sqrt{649}}{2*5}=\frac{-8+4\sqrt{649}}{10}
$