12r^2+139r-60=0

Solution for 12r^2+139r-60=0 equation:

12r^2+139r-60=0

a = 12; b = 139; c = -60;
Δ = b2-4ac
Δ = 1392-4·12·(-60)
Δ = 22201
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{22201}=149$
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(139)-149}{2*12}=\frac{-288}{24}
=-12
$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(139)+149}{2*12}=\frac{10}{24}
=5/12
$