20a^2+124a-288=0

Solution for 20a^2+124a-288=0 equation:

20a^2+124a-288=0

a = 20; b = 124; c = -288;
Δ = b2-4ac
Δ = 1242-4·20·(-288)
Δ = 38416
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{38416}=196$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(124)-196}{2*20}=\frac{-320}{40}
=-8
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(124)+196}{2*20}=\frac{72}{40}
=1+4/5
$