7x(x-1)=56

Solution for 7x(x-1)=56 equation:

7x(x-1)=56

We move all terms to the left:

7x(x-1)-(56)=0

We multiply parentheses

7x^2-7x-56=0

a = 7; b = -7; c = -56;
Δ = b2-4ac
Δ = -72-4·7·(-56)
Δ = 1617
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:

$\sqrt{\Delta}=\sqrt{1617}=\sqrt{49*33}=\sqrt{49}*\sqrt{33}=7\sqrt{33}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-7)-7\sqrt{33}}{2*7}=\frac{7-7\sqrt{33}}{14}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-7)+7\sqrt{33}}{2*7}=\frac{7+7\sqrt{33}}{14}
$