x(x-11x)+28=0

Solution for x(x-11x)+28=0 equation:

x(x-11x)+28=0

We add all the numbers together, and all the variables

x(-10x)+28=0

We multiply parentheses

-10x^2+28=0

a = -10; b = 0; c = +28;
Δ = b2-4ac
Δ = 02-4·(-10)·28
Δ = 1120
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:

$\sqrt{\Delta}=\sqrt{1120}=\sqrt{16*70}=\sqrt{16}*\sqrt{70}=4\sqrt{70}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-4\sqrt{70}}{2*-10}=\frac{0-4\sqrt{70}}{-20}
=-\frac{4\sqrt{70}}{-20}
=-\frac{\sqrt{70}}{-5}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+4\sqrt{70}}{2*-10}=\frac{0+4\sqrt{70}}{-20}
=\frac{4\sqrt{70}}{-20}
=\frac{\sqrt{70}}{-5}
$