4d^2-19d-30=0

Solution for 4d^2-19d-30=0 equation:

4d^2-19d-30=0

a = 4; b = -19; c = -30;
Δ = b2-4ac
Δ = -192-4·4·(-30)
Δ = 841
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$d_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$d_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{841}=29$
$d_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-19)-29}{2*4}=\frac{-10}{8}
=-1+1/4
$
$d_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-19)+29}{2*4}=\frac{48}{8}
=6
$