4k^2-24k-28=0

Solution for 4k^2-24k-28=0 equation:

4k^2-24k-28=0

a = 4; b = -24; c = -28;
Δ = b2-4ac
Δ = -242-4·4·(-28)
Δ = 1024
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$k_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$k_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1024}=32$
$k_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-24)-32}{2*4}=\frac{-8}{8}
=-1
$
$k_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-24)+32}{2*4}=\frac{56}{8}
=7
$