5x2+18x+8=0

Solution for 5x2+18x+8=0 equation:

5x^2+18x+8=0

a = 5; b = 18; c = +8;
Δ = b2-4ac
Δ = 182-4·5·8
Δ = 164
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:

$\sqrt{\Delta}=\sqrt{164}=\sqrt{4*41}=\sqrt{4}*\sqrt{41}=2\sqrt{41}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(18)-2\sqrt{41}}{2*5}=\frac{-18-2\sqrt{41}}{10}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(18)+2\sqrt{41}}{2*5}=\frac{-18+2\sqrt{41}}{10}
$