5k^2+6k-16=0

Solution for 5k^2+6k-16=0 equation:

5k^2+6k-16=0

a = 5; b = 6; c = -16;
Δ = b2-4ac
Δ = 62-4·5·(-16)
Δ = 356
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$k_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$k_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{356}=\sqrt{4*89}=\sqrt{4}*\sqrt{89}=2\sqrt{89}$
$k_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(6)-2\sqrt{89}}{2*5}=\frac{-6-2\sqrt{89}}{10}
$
$k_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(6)+2\sqrt{89}}{2*5}=\frac{-6+2\sqrt{89}}{10}
$