5x^2+5.25x+1=0

Solution for 5x^2+5.25x+1=0 equation:

5x^2+5.25x+1=0

a = 5; b = 5.25; c = +1;
Δ = b2-4ac
Δ = 5.252-4·5·1
Δ = 7.5625
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{-(5.25)-\sqrt{7.5625}}{2*5}=\frac{-5.25-\sqrt{7.5625}}{10}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(5.25)+\sqrt{7.5625}}{2*5}=\frac{-5.25+\sqrt{7.5625}}{10}
$