30x^2+39x-9=0

Solution for 30x^2+39x-9=0 equation:

30x^2+39x-9=0

a = 30; b = 39; c = -9;
Δ = b2-4ac
Δ = 392-4·30·(-9)
Δ = 2601
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2601}=51$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(39)-51}{2*30}=\frac{-90}{60}
=-1+1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(39)+51}{2*30}=\frac{12}{60}
=1/5
$