3a^2+10a-72=0

Solution for 3a^2+10a-72=0 equation:

3a^2+10a-72=0

a = 3; b = 10; c = -72;
Δ = b2-4ac
Δ = 102-4·3·(-72)
Δ = 964
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{964}=\sqrt{4*241}=\sqrt{4}*\sqrt{241}=2\sqrt{241}$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(10)-2\sqrt{241}}{2*3}=\frac{-10-2\sqrt{241}}{6}
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+2\sqrt{241}}{2*3}=\frac{-10+2\sqrt{241}}{6}
$