30x^2-11x-28=0

Solution for 30x^2-11x-28=0 equation:

30x^2-11x-28=0

a = 30; b = -11; c = -28;
Δ = b2-4ac
Δ = -112-4·30·(-28)
Δ = 3481
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3481}=59$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-11)-59}{2*30}=\frac{-48}{60}
=-4/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-11)+59}{2*30}=\frac{70}{60}
=1+1/6
$