4n^2-12n-55=0

Solution for 4n^2-12n-55=0 equation:

4n^2-12n-55=0

a = 4; b = -12; c = -55;
Δ = b2-4ac
Δ = -122-4·4·(-55)
Δ = 1024
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1024}=32$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-32}{2*4}=\frac{-20}{8}
=-2+1/2
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+32}{2*4}=\frac{44}{8}
=5+1/2
$