7x^2-56x+56=0

Solution for 7x^2-56x+56=0 equation:

7x^2-56x+56=0

a = 7; b = -56; c = +56;
Δ = b2-4ac
Δ = -562-4·7·56
Δ = 1568
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:

$\sqrt{\Delta}=\sqrt{1568}=\sqrt{784*2}=\sqrt{784}*\sqrt{2}=28\sqrt{2}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-56)-28\sqrt{2}}{2*7}=\frac{56-28\sqrt{2}}{14}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-56)+28\sqrt{2}}{2*7}=\frac{56+28\sqrt{2}}{14}
$