12x^2-136x+280=0

Solution for 12x^2-136x+280=0 equation:

12x^2-136x+280=0

a = 12; b = -136; c = +280;
Δ = b2-4ac
Δ = -1362-4·12·280
Δ = 5056
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{5056}=\sqrt{64*79}=\sqrt{64}*\sqrt{79}=8\sqrt{79}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-136)-8\sqrt{79}}{2*12}=\frac{136-8\sqrt{79}}{24}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-136)+8\sqrt{79}}{2*12}=\frac{136+8\sqrt{79}}{24}
$