5c^2-50c+55=0

Solution for 5c^2-50c+55=0 equation:

5c^2-50c+55=0

a = 5; b = -50; c = +55;
Δ = b2-4ac
Δ = -502-4·5·55
Δ = 1400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$c_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$c_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{1400}=\sqrt{100*14}=\sqrt{100}*\sqrt{14}=10\sqrt{14}$
$c_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-50)-10\sqrt{14}}{2*5}=\frac{50-10\sqrt{14}}{10}
$
$c_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-50)+10\sqrt{14}}{2*5}=\frac{50+10\sqrt{14}}{10}
$