26f^2+36f=108

Solution for 26f^2+36f=108 equation:

26f^2+36f=108

We move all terms to the left:

26f^2+36f-(108)=0

a = 26; b = 36; c = -108;
Δ = b2-4ac
Δ = 362-4·26·(-108)
Δ = 12528
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$f_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$f_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{12528}=\sqrt{144*87}=\sqrt{144}*\sqrt{87}=12\sqrt{87}$
$f_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(36)-12\sqrt{87}}{2*26}=\frac{-36-12\sqrt{87}}{52}
$
$f_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(36)+12\sqrt{87}}{2*26}=\frac{-36+12\sqrt{87}}{52}
$